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Preservation of intelligibility and acoustical characteristics in partial laryngectomees and normal laryngeal speakers produced under conditions of competing noise

Gerdeman, Bernice Smith, Ph.D.

The Ohio State University, 1992

UMI 300 N. ZeebRd. Ann Arbor, MI 48106

PRESERVATION OF INTELLIGIBILITY AND ACOUSTICAL CHARACTERISTICS IN PARTIAL LARYNGECTOMEES AND NORMAL LARYNGEAL SPEAKERS PRODUCED UNDER CONDITIONS OF COMPETING NOISE

DISSERTATION

Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of the Ohio State University

Bernice Smith Gerdeman, B.S., M.A.

afc s|c >|e * *

The Ohio State University

1992

Dissertation Committee: Approved by

Michael D. Trudeau, Ph.D. * . . . * «.____ a Robert Allen Fox, Ph.D. Dennis K. Pearl, Ph.D. Adviser Division of Speech and Hearing Science Copyright by Bernice Smith Gerdeman 1992 To My Family and Friends

For their love and continued support.

To My Patients

Who have had trust and faith in me and who have been valuable teachers. ACKNOWLEDGEMENTS

There are a number of individuals to whom I would like to extend my deepest appreciation for without their expertise this project would not have be possible. I would like to thank my adviser, Michael D. Trudeau, Ph.D. for his support and direction throughout this dissertation. To my committee members,

Dennis K Pearl, Ph.D. for his direction and guidance on statistical design, and

Robert A. Fox, Ph.D. for his support and constructive advice. A special thanks to Reiner Wilhelms, Ph.D. for his support, encouragement and direction with programing and helping analyze my acoustical data.

I would like to thank James A. Mechenbier, M.D., David E. Schuller,

M.D., and David R. Kelly, M.D. for their help in identifying the hemilaryngectomy and supraglottic laryngectomy speakers in this study.

My gratitude extends to Claude Lambert, M.A. for his source of technical information, assistance and encouragement. Eric LaPresto, M.S., helped with management of my large data sets and with training in using the Sun computer system.

My appreciation extends to the OSU Statistical Consuting Service where

Rob Leighty, Ph.D. and Mr. Yuangen Zhu provided the help needed to complete the statistical analysis of this investigation. I am very grateful to have worked with William J. Collins, Ph.D. during the last few years of this investigation as his graduate administrative associate. I have gained valuable knowledge from his administrative skills and his overall positive nature. His support and encouragement has been dearly appreciated.

I would like to acknowledge Osamu Fujimura, D.Sc. for his support and encouragement throughout this investigation. His expertise was invalueable in helping me with the instrumentation and signal processing software.

A heartfelt thanks is extended to Howard Wingert who was there when I needed someone to listen, to provide emotional support, and to help me maintain a positive focus. VITA

August 25, 1950 ...... Bom - Lima, Ohio

1972 ...... B.S., The Ohio State University Columbus, Ohio 1972 - 1982 ...... Speech - Language Pathologist Columbus Public Schools, Columbus, Ohio

1982 - 1983 ...... Account Representative, Lanier Business Products, Inc,Columbus, Ohio

Summer 1985 ...... Doctoral Trainee, Veteran's Administration Medical Center, Cincinnati, Ohio

1985 ...... M.A., Speech - Language Pathology, The Ohio State University, Columbus, Ohio

1988 - 1991 ...... Speech - Language Pathologist, Grant Medical Center, Columbus, Ohio

1991 - 1992 ...... Voice Pathologist, Institute for Voice Analysis, and Rehabilitation, Dayton, Ohio

PUBLICATIONS

Neils, J. , Brennan, M.M., Cole, M., Boiler, F., & Gerdeman, B. (1988). The use of phonemic cueing with Alzheimer’s disease patients. Neuropsvcholoeia. 16, 351-354.

FIELD OF STUDY

Major Field: Speech and Hearing Science

v TABLE OF CONTENTS

DEDICATION ...... ii

ACKNOWLEDGEMENTS...... iii

VITA ...... v

LIST OF TABLES...... ix

CH A PTER 1...... 1

I. IN TRO D U CTIO N ...... 2

A Statement of the Problem ...... 3 Questions to be Investigated ...... 6 Glossary of Terms...... 7

CHAPTER II...... 9

E. REVIEW OF LITERATURE...... 9

H istory...... 9 Anatomic Regions of Larynx ...... 10 Conservation Laryngeal Surgery ...... 10 Partial Horizontal Laryngectomy ...... 12 Vertical Partial Laryngectomy...... 12 Perceptial Characteristics of Partial Laryngectomy...... 13 Acoustical Characteristics of Partial Laryngectomy...... 16 S u m m ary ...... 20

CHAPTER IE ...... 22

III. METHODS...... 22

Speaking Subjects...... 23 Materials...... 24 Selection of Verbal Stimuli ...... 24 Generating The Noise Tape ...... 25 Procedures ...... 25 Calibration Procedures ...... 25 Recording Instrumentation ...... 26 Recording the Speakers ...... 27 Playback of N oise...... 27 v i Listening Task ...... 28 Listeners ...... 28 Generating The Listening Tapes ...... 28 Presentation of the Speaker Tapes to Listeners ...... 34 Procedure for the Listeners ...... 35 Scoring of the Listener's Responses ...... 36 Reliability of Measurements ...... 37 Reliability of Reference Tone and Noise Generated Signal ...... 37 Acoustical Analyses ...... 38 Reliability in the Segmentation of the Acoustical Stimuli ...... 40 Acoustic Onsets and Offsets ...... 42 Statistical Analyses ...... 45

CHAPTER IV ...... 47

IV. RESULTS AND DISCUSSION...... 47

Descriptive Statistics of Intelligibility ...... 47 Group Means by Speaker Type ...... 48 Group Means by Speaker Type and Context Predictability ...... 49 Group Means by Speaker Type and Competing Noise ...... 51 Group Means by Speaker Type, Context Predictability, and Competing Noise...... 52 S u m m ary ...... 55 Logistic Regression...... 56 S u m m ary ...... 65

Descriptive Statistics of Acoustic Measures ...... 66 Intensity ...... 66 Duration ...... 78 Fundamental Frequency ...... 92 V o ic in g...... 103 Principal Components Analyses of Acoustical Parameters ... 116 Inten sity ...... 116 Mean Fundamental Frequency ...... 117 Percentage of voicing ...... 118 D uration ...... 119 General Linear Model ...... 120 Sum m ary ...... 126 Overall Interpretation of Intelligibility ...... 131 CHAPTER V 139

V. SUMMARY AND CONCLUSIONS...... 139

Implications for Clinical Use ...... 140 Suggestions For Future Research...... 141

APPENDICES

A. Speaker Information ...... 143 B. Speaker's Consent To Investigational Procedure ...... 147 C. Instructions For Listeners and Response Forms ...... 149 D. Listener's Consent To Investigational Procedure ...... 170 E. Mean and Standard Deviations For Each Individual Speaker Group...... 173 F. Descriptive Statistics For The Dependent Acoustical Variables by Each Speaker...... 177 G. Medical Information of Post Surgery Speakers ...... 202 H. Example of Marked Sentence Using Waves+ ...... 205 I. Example of Marked Word Using Waves+ ...... 207 J. Example of Marked Vowel Nucleus Using Waves + ...... 209

BIBLIOGRAPHY...... 211

viii LIST OF TABLES

TABLE PAGE

1. RMS for reference signals per speaker ...... 33

2. Intelligibility as a function of speaker type ...... 48

3. Intelligibility among speaker types as a function of context predictability ...... 49

4. Intelligibility among speaker types as a function of competing noise ...... 51

5. Intelligibility among speaker types as a function of context predictability and competing noise ...... 52

6. Summary of logistic regression models including degreesof freedom, log likelihood, improvement in Chi-sq., goodness of fit Chi-square, and p-values statistics of either entering or removing terms from the model ...... 59

7. Log-Likelihood, Chi-Square, degrees of freedom (df), and p-values for the final model using logistic regression ...... 60

8. Estimated odds and 95% Cl for the four possible combinations of variables noise condition andcontext predictability for normal speakers. Conversion of the odds into percentages ...... 62

ix 9. Estimated odds and 95% Cl for the four possible combinations of variables noise condition and context predictability for supraglottic laryngectomy speakers. Conversion of the odds into percentages ...... 62

10. Estimated odds and 95% Cl for the four possible combinations of variables noise condition and context predictability for hemilaryngectomy speakers. Conversion of the odds into percentages ...... 63

11. Overall Means and Std. Dev. (SPL) of intensity of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition ...... 67

12. Overall Means and Std. Dev. (SPL) of intensity of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability ...... 73

13. Overall Means and Std. Dev. (SPL) of intensity of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition ...... 74

14. Overall Means and Std. Dev. (SPL) of intensity by noise condition as a function of context predictability ...... 75

15. Overall Means and Std. Dev. (SPL) of intensity for the sentence, key word and vowel nucleus as a function of noise ...... 76

16. Overall Means and Std. Devs. (SPL) of intensity for the sentence, key word and vowel nucleus as a function of context predictability ...... 77

17. Overall Means and Std. Dev. (SPL) of intensity for the sentence, key word and vowel nucleus as a function of speaker type...... 77

x 18. Overall Means and Std. Dev. (ms) of duration of the sentence, key word and vowel nucleus among speaker types as a function of context predictability and noise condition ...... 79

19. Overall Means and Std. Dev. (ms) of duration of the sentence, key word and vowel nucleus among speaker types as a functionof context predictability ...... 85

20. Overall Means and Std. Dev. (ms) of duration of the sentence, key word and vowel nucleus among speaker types as a function of noise condition ...... 87

21. Overall Means and Std. Dev. (ms) of duration by noise condition as a function of context predictability ...... 88

22. Overall Means and Std. Dev. (ms) of duration for the sentence, key word, and vowel nucleus as a function of noise ...... 89

23. Overall Means and Std. Dev. (ms) of duration for the sentence, key word, and vowel nucleus as a function of context predictability ...... 89

24. Overall Means and Std. Dev. (ms) of duration for the sentence, key word, and vowel nucleus as a function of speaker type...... 90

25. Overall Means and Std. Dev. of fundamental frequency (Hz) of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition ...... 91

26. Overall Means and Std. Dev. of fundamental frequency (Hz) of the sentence, key word, and vowel nucleus among speaker type as a function of context predictability ...... 97

xi 27. Overall Means and Std. Dev. of fundamental frequency (Hz) of the sentence, key word, and vowel nucleus among speaker type as a function of noise condition ...... 99

28. Overall Means and Std. Dev. of fundamental frequency (Hz) by noise condition as a function of context predictability 100

29. Overall Means and Std. Dev. of fundamental frequency (Hz) for the sentence, key word, and vowel nucleus as a function of noise condition ...... 101

30. Overall Means and Std. Dev. of fundamental frequency (Hz) for the sentence, key word and vowel nucleus as a function of context predictability ...... 102

31. Overall Means and Std. Dev. of fundamental frequency (Hz) for the sentence, key word, and vowel nucleus as a function of speaker type ...... 103

32. Overall Means and Std. Dev of percentage of voicing for the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition ...... 104

33. Overall Means and Std. Dev of percentage of voicing for the sentence, key word, and vowel nucleus among speaker types as a function of context predictability ...... 110

34. Overall Means and Std. Dev of percentage of voicing for the sentence, key word, and vowel nucleus among speaker types as a function of noise condition ...... I l l

35. Overall Means and Std. Dev of percentage of voicing by noise condition as a function of context predictability ...... 112

xii 36. Overall Means and Std. Dev of percentage of voicing for the sentence, key word, and vowel nucleus as a function of noise ...... 114

37. Overall Means and Std. Dev. of percentage of voicing for the sentence, key word, and vowel nucleus as a function of context predictability ...... 114

38. Overall Means and Std. Dev. of percentage of voicing for the sentence, key word, and vowel nucleus as a function of speaker type...... 115

39. Unrotated factor matrix and eigenvalues of intensity measures...... 117

40. Unrotated factor matrix and eigenvalues of mean fundamental frequency measures ...... 118

41. Unrotated factor matrix and eigenvalues of percentage of voicing measures...... 119

42. Unrotated factor matrix and eigenvalues of duration measures...... 120

43. Summary of the General Linear Model of the effect of the acoustical variables (decibels, fundamental frequency mean ) on the perceptual variable (log odds correct) ...... 125

44. Normal speaker information for age and three frequency average for right and left ear ...... 144

45. Supraglottic laryngectomy speaker information for age and three frequency average of right and left ear, time since surgery, and stage of surgery...... 145

xiii 46. Hemilaryngectomy speaker information for age and three frequency average of right and left ear, time since surgery, and stage of surgery...... 146

47. Descriptive statistics from the percentage correct for normal speakers in the no noise-high predictability condition, no noise-low predictability condition, noise-high predictability condition, & noise-low predictability condition ...... 174

48. Descriptive statistics from the percentage correct for the hemilaryngectomy speakers in the no noise-high predictability condition, no noise-low predictability condition, noise-high predictability condition, & noise-low predictability condition ...... 175

49. Descriptive statistics from the percentage correct for supraglottic laryngectomy speakers in the no noise-high predictability condition, no noise-low predictability condition, noise-high predictability condition, & noise-low predictability condition ...... 176

50. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for normal speakers in the no noise-low predictability condition ...... 178

51. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for normal speakers in the no noise-low predictability condition ...... 179

52. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for normal speakers in the no noise-high predictability condition ...... 180

xiv 53. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for normal speakers in the no noise-high predictability condition ...... 181

54. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, of duration of the sentence, key word, & vowel nucleus for normal speakers in the noise-low predictability condition ...... 182

55. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for normal speakers in the noise-low predictability condition ...... 183

56. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for normal speakers in the noise-high predictability condition...... 184

57. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for normal speakers in the noise-high predictability condition ...... 185

5 8. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the no noise-low predictability condition ...... 186

59. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the no noise-low predictability condition ...... 187

xv 60. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the no noise-high predictability condition ...... 188

61. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the no noise-high predictability condition ...... 189

62. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the noise-low predictability condition ...... 190

63. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the noise-low predictability condition ...... 191

64. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the noise-high predictability condition ...... 192

65. Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for hemilaryngectomy speakers in the noise-high predictability condition ...... 193

66. Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for supraglottic laryngectomy speakers in the no noise-low predictability condition ...... 194

xvi Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for supraglottic laryngectomy speakers in the no noise-low predictability condition ......

Descriptive statistics from the acoustical measures of intensity of the sentence, key word, & vowel nucleus, and of duration of the sentence, key word, & vowel nucleus for supraglottic laryngectomy speakers in the no noise-high predictability condition ......

Descriptive statistics from the acoustical measures of fundamental frequency of the sentence, key word, & vowel nucleus, and of percentage of voicing of the sentence, key word, & vowel nucleus for supraglottic laryngectomy speakers in the no noise-high predictability condition ......

Medical information on supraglottic laryngectomy speakers......

Medical information on hemilaryngectomy speakers... xvii CHAPTER I

INTRODUCTION

Alteration of the laryngeal physiology due to surgical treatment of carcinoma changes the perceptual and acoustic characteristics of the voice.

These changes may range from mild to severe degradation of the speech signal.

There are limitations of communicative ability depending on the amount of surgical resection. These limitations are quite apparent when the total larynx is excised; however, the effects of more conservative surgical procedures with some of the phonatory function of the larynx preserved are less well documented.

In the United States, the estimated annual incidence of new cases of laryngeal cancer is 12,500, consisting of 10,000 new cases for males and 2,500 for females (American Cancer Society, 1991). These incidence estimates are based on rates from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program 1985-1987. Although cancer of the larynx is not one of the most prevalent cancers, cancer of the larynx is one of the more common malignancies of the head and neck region (Pilch, Brodsky, and

Goodman, 1988). In the United States, cancer of the glottis is slightly more prevalent than cancer of the supraglottis (Cann, Rothman, and Fried, 1988) which is also the pattern in Great Britain (Lederman, 1970). Although survival

1 decreases with age (Baranovsky and Myers, 1986) and extent of the disease

(Myers and Hanky, 1982), the five-year survival rate for cancer of the larynx is over 80 percent if detected early and treated promptly through conservation surgical methods. For more advanced cancers, the five-year survival rate varies from 26 percent to 52 percent, depending on lymph node involvement and/or metastases to distal organs (American Cancer Society, 1987).

Medical advancements in both detection and treatment of laryngeal cancer have produced longer survival periods for the cancer patient. In cancers that are detected early, more conservative management is offered to the individual allowing for surgical removal or radiation of the cancer. Either treatment preserves the larynx and voice.

Laryngeal resection that involves removal of only a portion of the larynx is referred to as conservation laryngeal surgery. Hemilaryngectomies can include a vertical partial laryngectomy (herein after hemilaryngectomy) involving removal of one half or possibly more of the larynx in the vertical plane, or a horizontal partial laryngectomy (herein after supraglottic laryngectomy) that involves the removal of the supraglottic portion of the larynx (epiglottis and false cords)

(Deweese, Saunders, Schuller, and Schleuning, 1988). According to Ogura and

Biller (1971), partial laryngeal resection can be performed in 70 percent of all cases with laryngeal cancer and a three-year absolute survival rate has been reported as 76 percent.

Partial laryngeal resection alters the anatomical structure of the larynx, thus affecting vocal quality. Distortion of the laryngeal anatomy diminishes secretions leading to dryness and vocal irritation. Although the larynx is preserved and the individual retains the ability to speak, varying degrees of hoarseness (Fried, 1988; Koike, Iwai & Morimoto, 1975), breathiness and roughness (Blaugrund, Gould, Tomoyuki, Meltzer, Bloch, & Baer, 1984;

Hirano, Kurita, & Matsuoka, 1987; Leeper, Heeneman, & Reynolds, 1990) are evident. When cancer involves removal of an entire true vocal cord, vocal quality deteriorates further (DeWeese, et. al., 1988).

A return to a lifestyle that is as close to normal as possible is a goal for the rehabilitation team working with an individual who has had cancer of the larynx.

This includes the Speech-Language Pathologist's goal to "achieve the maximum speech intelligibility possible within the constraints of remaining structure and function or to devise an alternative mode of expression when functional speech is infeasible" (p 279, Trudeau, 1988).

Successful treatment for laryngeal carcinoma encompasses long term survival of the patients and raises the issue of the patient’s quality of life once medical management is complete. Many investigators have addressed the psychosocial impact of total laryngectomy (Gardner, 1966; Amster, Love,

Menzel, Sandler, Sculthorpe, & Gross, 1972; Gilmore; 1974; Byles, Fomer, &

Stemple, 1985; Natvig, 1983). Although there are few studies of the effects of partial laryngectomy procedures on speech, alteration of voice and speech are noticeable and lasting consequences to laryngeal cancer (Boone, 1983).

A Statement of the Problem

Communicative situations arise daily that involve listening conditions that are less than optimal. Often environmental noises can interfere with the understanding of speech. If background noises become intense enough, speakers must vocally exert themselves in order to be understood. Examples of noisy settings could include restaurants, small or large social gatherings, busy 4 street comers, parties, factories, etc.. In 1909, Lombard noted that a speaker in ambient noise conditions will increase the intensity of speech and when the noise stops the speaker will lower the intensity to its former level (the Lombard effect).

A large body of research pertaining to the various characteristics of the Lombard effect has been summarized by Lane and Tranel (1971). In their article, Lane and Tranel (1971) reported that Etienne Lombard in the early 1900's noted a direct relationship between the amount of background noise and voice level: the higher the noise level, the greater the vocal intensity. Normal speakers in adverse noise conditions make reflexive changes when speaking to deliver the message intelligibly, i.e., intensity increases, rate of speech decreases and articulatory changes such as a decrease in syllable duration occur (Zeine &

Brandt, 1988). A partial laryngectomy with its effects on voice connotes decreased performance in the ability to increase vocal intensity; thereby, decreasing the intelligibility of speech during adverse background noise causing a breakdown between the speaker and listener. No study has investigated the effect of background noise as it relates to intelligibility in partial laryngectomees as compared to normal speakers.

Most of the research investigating intelligibility of speech involving surgical procedures of the larynx has been with alaryngeal speakers using various speech modes such as esophageal speech, artificial devices, or surgical reconstruction (with or without a voice prosthesis). Previous research has failed to control for possible speaker's adjustments to background noise. Additionally past investigations have not addressed the listeners' ability to use semantic contextual cues and syntactic cues in judging the intelligibility of the speakers.

In intelligibility studies of alaryngeal speakers, investigators subjected the listeners to auditory competition but did not expose the speakers to the same noise condition. In a pilot study, this investigator (1985) utilized test stimuli containing high predictability and low predictability key sentences from the

Speech Perception In Noise Test (Kalikow, Stevens, and Elliot, 1977) to assess intelligibility in competing noise among various alaryngeal speakers. When developing this test, Kalikow, et. al. took into account that normal adults utilize both acoustic-phonetic and linguistic-contextual cues for speech recognition, and that everyday communication occurs with some background noise present.

These sentences provided phonologic, semantic contextual cues, and syntactic cues to aid the listener.

The results of this pilot study suggested that speakers adjusted their speech in the presence of increasing ambient noise conditions for the high predictability and low predictability sentences such that, despite increasing noise, the speakers were successful in preserving speech intelligibility.

In summary this investigation will attempt to, (1) determine to what degree individuals who undergo a partial laryngectomy successfully preserve intelligibility in increasing background noise and (2) address the acoustic characteristics of voice and speech in relationship to intelligibility of the speakers.

Three groups of speakers, normal laryngeal, hemilaryngectomees, and supraglottic laryngectomees read randomly selected sentences from the Speech

Perception In Noise Test (Kaliko, et. al., 1977) under two conditions of competing noise: no noise and 75 dB SPL white noise. These sentences were played randomly to naive listeners to obtain perceptual data. Analyses of listener's responses gave an intelligibility percentage for each speaker.

Acoustical analyses of the speakers' recordings determined what characteristics appeared to be altered when intelligibility was impaired. This research provided insight into developing strategies that may aid a person who has undergone a partial laryngectomy to become more intelligible in various communicative settings and added to our knowledge and understanding of the dynamics of speech in the partial laryngectomy.

Questions to be Investigated

This study was designed to investigate the following questions:

4. What selected acoustical features (vocal fundamental frequency, vocal intensity, segment duration, and percentage of voicing) help in predicting 7 intelligibility of speech among vertical partial laryngectomees, horizontal partial laryngectomees, and normal speakers as a function both of competing noise in the speaking/listening environment and of the strength of contextual cues.

Glossary of Terms

In order to provide a reference the following terms will be used in this study.

1. Alaryngeal - without a larynx.

2. Fundamental frequency (Fo) - the rate at which a waveform is

repeated per unit of time, measured in Hz (Baken, 1987).

3. Horizontal partial laryngectomy (supraglottic laryngectomy) - excision of the larynx above the level of the true vocal cords involving the epiglottis, arytenoepiglottic folds, arytenoids, and ventricular bands (false cords). The true vocal cords are preserved (DeWeese, et. al., 1988).

4. Intelligibility - a judgment by the listener of what the speaker said and what was actually said.

5. Predictability - referring to the SPIN Test, the use of semantic contextual cues to predict the final word in the sentence.

High predictability - the last word in the SPIN Test

sentences is predicted using syntactic, semantic and prosodic cues within the sentence; i.e. 'Hit

the baseball with a I2M' (Kalikow, et.al., 1977).

Low predictability - the last word in the SPIN Test

sentences that is difficult to predict because the

listener must depend on acoustic and lexical

cues; i.e. 'John was talking about the bay'

(Kalikow, et.al., 1977).

6. Vertical partial laryngectomy (hemilaryngectomy) - excision of half or more of the larynx in the vertical plane involving one true vocal cord or one true vocal cord and a portion of the other (DeWeese. et. al., 1988).

7. Post surgical group - individuals who participated in this study who have undergone either a horizontal partial or a vertical partial laryngectomy for removal of laryngeal carcinoma. CHAPTER II

REVIEW OF LITERATURE

The purpose of this study was to investigate the effectiveness with which two groups of individuals preserve the intelligibility of their speech under two conditions of competing noise; no noise and 75dB SPL of white noise, and to describe the acoustical variables that influence speaker intelligibility among these groups. The two groups of individuals had either undergone a hemilaryngectomy or a supraglottic laryngectomy. For comparison purposes there was a control group of age matched normal speakers.

History

Over a century has passed since Theodor Billroth performed the first total laryngectomy for cancer in 1873. Two years later Billroth reported the first hemilaryngectomy for cancer (Billroth, 1930). This was the beginning for conservation laryngeal surgery. Initially, surgical techniques were crude and poorly formulated resulting in high mortality rates. As detection and treatment of laryngeal cancer have improved so have the survival periods for the cancer

9 10 patient. In cancer that is detected early, more conservative management is offered to the individual allowing for surgical resection or radiation of the cancer. Either treatment preserves the larynx and voice (Eliachar, Papay, &

Tucker, 1991).

Anatomic Regions of the Larynx

Thoughout the years an effort was made to define the anatomic boundaries of the various laryngeal areas and in 1974 at the Centennial Conference on

Laryngeal Cancer definitions of laryngeal boundaries were established. The larynx is divided into three anatomic regions: the supraglottis, glottis, and subglottis. According to the American Joint Committee on Cancer (1988), the supraglottis is composed of the epiglottis (both the lingual and laryngeal area), aryepiglottic folds, arytenoids, and ventricular bands (false cords). The inferior border of the supraglottis is an arbitrary horizontal plane passing through the apex of the ventricle. The glottis is made up of the true vocal cords, including the anterior and posterior commissures, with the lower boundary taken as a horizontal plane 1 cm below the apex of the ventricle. The subglottis is the region extending from the lower boundary of the glottis to the lower margin of the cricoid cartilage. When early laryngeal cancers are confined to an anatomic compartment then limited surgical procedures can be performed to resect the primary tumor and conserve sufficient tissue to maintain an adequate airway and preserve swallowing and voice (Eliachar, Papay, & Tucker, 1991).

Conservation Laryngeal Surgery

Laryngeal resection that involves partial removal of the larynx to eradicate local disease while preserving a portion of the larynx is referred to as conservation laryngeal surgery (DeWeese, Saunders, Schuller, and Schleuning,

1988). The basis for conservation laryngeal surgery for cancer rests in the embiyologic development and the anatomic compartmentalized lymphatic drainage of the larynx (Maceri, Lampe, Makielshi, Passamani, Krause, 1985;

Lawson and Biller, 1985). The three anatomical regions serve as barriers to the vertical spread of tumors and once the neoplasm is confined to a certain area the pattern of spread differs at each anatomic site (Lawson and Biller, 1985).

Embryologically, the supraglottic larynx develops from the buccopharyngeal anlage (arches HI and IV) while the glottic and subglottic areas derive from the tracheobronchial anlage (arches V and VI) both supporting separate lymphatic circulations (Hast, 1976). In 1956, Pressman used dyes and radioisotope tracers to demonstrate the pathways of the submucosal lymphatics of the larynx. This study showed the compartmentalization of the lymphatic system which influences the spread of laryngeal neoplasms. Dye injected into the supraglottis showed a division superiorly and inferiorly (Pressman, 1956) as well as a division of the right and left hemilarynges (Pressman, Simon and

Morrell, 1960). This concept of different lymphatic drainages has also been pointed out by Bocca, Pignataro, & Mosciaro, (1968) and Kirchner and Som

(1971).

All laryngeal malignancies are classified and staged by the American Joint

Committee on Cancer (1988). This system classifies carcinoma according to the tumor size of the supraglottis, glottis, and subglottis along with any nodal involvement and distant metastasis. Stage groupings range from Stage 0 to

Stage IV. 1 2 Partial Horizontal Laryngectomy

Partial horizontal laryngectomy represents a conservation procedure that removes malignancies above the level of the glottis without sacrificing the normal functions of the remaining larynx (Lawson and Biller, 1985, DeWeese, et. al., 1988). The technique of the surgery depends on the extent of the procedure and may involve removal of the entire epiglottis, hyoid bone, preepiglottic space, false vocal folds and the upper half of the thyroid cartilage.

The technique may include supraglottic laryngectomy, extended supraglottic laryngectomy, and partial laryngopharyngectomy (Tucker, 1987).

Vertical Partial Laryngectomy

There are a variety of procedures available for individuals with glottic carcinoma that has extended to the vocal process of the arytenoid or to the anterior commissure and/or the contralateral true vocal cord (Bailey, 1982). The four basic procedures classified as vertical partial laryngectomy used to treat glottic carcinomas include: (1) laryngofissure with cordectomy; (2) hemilaryngectomy, (3) extended or frontolateral vertical partial laryngectomy, and (4) near-total laryngectomy (Tucker, 1987; Bailey, 1985). Glottic tumors are usually detected early due to the hoarse voice quality produced even with a very small lesion (Pilch, Brodsky, & Goodman, 1988). When carcinoma of 1 to 5 mm in size is limited to one membraneous vocal fold a simple cordectomy via a laryngofissure is performed. A hemilaryngectomy is the resection of all of one membraneous vocal fold and, if necessary, the arytenoid cartilage as well as a few millimeters of the opposite vocal fold. A frontolateral vertical partial laryngectomy is performed when tumors involve the anterior commisure and all or part of both membranous vocal folds (Tucker, 1987; Eliachar, Papay, & Tucker, 1991). Extensive carcinoma in the glottic area is sometimes managed using a near-total laryngectomy. In this technique, all of the glottic region is resected with the exception of one arytenoid and one-half of the posterior commissure area. The surgically removed defect is then reconstructed using the epiglottis (Tucker, 1987; Schechter, 1983). Pearson, 1985, extensively describes the near-total laryngectomy technique that extends the vertical hemilaryngectomy to include sections of the cricoid and perilaryngeal tissue for excision of the tumor. The posterior commissure and one intact and mobile arytenoid with its ventricle is preserved. This procedure requires a trachea stoma for respiration and establishes a new sound source by constructing a valved shunt from remaining tissue for the patient to voice .

Perceptual Characteristics of a Partial Laryngectomy

One of the advantages of conservation laryngeal surgery is the preservation of the individual’s voice. Once surgery is performed these individuals regain voicing although it may be altered in comparison to their pre-cancerous original voice. Unlike the patient who undergoes a total laryngectomy and requires vocal restoration and follow-up by a speech pathologist, a patient who sustains a partial laryngectomy is seldom seen for voice training even if vocal rehabilitation is recommended for these patients (Bailey, 1982). This may be the reason for what appears to be a lack of research on vocal rehabilitation for persons who have received a partial laryngectomy. Very few articles were found in the literature which researched the intelligibility of individuals following conservation laryngeal surgery.

Over the years surgeons have subjectively reported effects on phonation following a partial laryngectomy. Maceri, Lampe, Makielski, Passamani, and 1 4 Krause (1985) reported that voice quality was independent of the type of conservation surgery. These findings were based on subjective physicians' reports of 21 patients who underwent a vertical hemilaryngectomy and 33 patients who underwent a supraglottic laryngectomy. In each group, it was reported that one third had good to excellent voice which was easily understood, one third had weak to breathy but serviceable voice and one third had poor or barely audible voice. It should be noted that the poor to barely audible group were patients who had a tracheostomy and spoke by occluding the tracheostomy tube. It was noted by Laceourreye, Laccourreye, Weinstein, Menard, and

Brasnu, (1990), that thirty-five out of thirty-six patients who underwent a partial laryngectomy were phonating within the first month after surgery with a breathy vocal quality comparable to someone with chronic laryngitis but adequate for social interaction. In reviewing medical charts over a twelve year period,

Rothfield, Johnson, Myers, and Wagner (1989), reported 53 out of 54 patients who underwent a hemilaryngectomy were subjectively judged as having a good voice. "Voice quality was based subjectively on the ability to converse intelligibly". The single patient that did not achieve a good voice in their study had a whisperlike but serviceable voice.

Liu, Ward, and Pleet, (1986), subjectively compaired the voice quality of

38 patients who underwent a partial laryngectomy with imbrication reconstruction with 16 patients who underwent a vertical hemilaryngectomy.

These investigators found that 35 out of 38 patients who had the imbrication reconstitution following a partial laryngectomy had good to excellent voice quality as compaired to 8 out of 16 patients following a vertical hemilaryngectomy. It was reported that the retention of the arytenoid provided a better voice. Ten laryngologists responded to a questionnaire regarding voice quality following a partial laryngectomy (Moore 1975). Moore concluded that "the excellence of voice varies directly with the capacity of the larynx for adductive closure", therefore, supraglottic laryngectomy procedures would have little effect on voice, but hemilaryngectomy surgery would cause hoarseness or breathiness and reduced vocal intensity. Breathiness was also noted as a result of incomplete glottic closure by Blakeslee, Vaughan, Shapshay, Simpson, &

Strong, (1984) or the shape of resulting scars after surgery (Brodnitz and

Conley 1967). Voice quality was judged to be rough due to irregular vibrations, breathy due to incomplete glottic closure, and strained or constricted secondary to hyperfunctioning of the supraglottic structures (Hirano, 1981; Hirano, Kurita,

& Marsuoka, 1987; Leeper, Heeneman, & Reynolds, 1990).

Looking at vocal quality in 68 patients who underwent various surgical procedures, Sessions, (1986) reported that individuals who underwent a partial vertical hemilaryngectomy had the most affect on voice quality . Of the 30 patients in this category, 52 percent had moderate to severe breathiness, 48 percent had moderate to severe harshness and 63 percent were rated with moderate to severe hoarseness. Breathiness was reported to have had the most adverse effect on speech intelligibility.

An intelligibility study found in the literature compared three normal speakers to three patients who underwent laryngeal conservation surgery and three patients who spoke with an artificial speech device (Rizer, Schechter, &

Coleman, 1984). Intelligibility scores ranged from approximately 95% to 100% for the normal speakers, 78% to 95% for the three conservation surgery patients and 58% to 78% for the three individuals who used an artificial speech aid. In this study 50 monosyllabic recorded words were played to a group of listeners in 1 6 a quiet room. The listeners were asked to circle the word they heard from a list of five printed words. It is important to note that the three individuals in the conservation surgery group had different surgeries which included a standard hemilaryngectomee, a frontolateral hemilaryngectomy, and a supraglottic laryngectomee.

Acoustical Characteristics of a Partial Laryngectomy

Very few studies have objectively investigated the acoustical aspects of individuals who have undergone conservative laryngeal surgery. Logemann

(1985) reported that some patients with a hemilaryngectomy exhibited high fundamental frequencies in the range of 150 to 160 Hz. This increase in the fundamental frequency may be attributed to increase muscle effort in the laryngeal area to achieve glottic closure and obtain a "clearer" less breathy vocal quality. In individuals who have undergone a supraglottic laryngectomy,

Logemann reported speech and voice changes can occur if the surgery extends anteriorly into the base of the tongue or inferiorly into the arytenoid cartilage or true vocal cord. Usually individuals do not complain of an impaired voice following a supraglottic laryngectomy (Burstein & Calcaterra, 1985).

Videolaryngoscopy examinations and objective phonatory function testing including acoustic and aerodynamic measurements were reported by Blaugrund, et. al. (1984) on twenty patients who underwent a vertical hemilaryngectomy and by Leeper, et. al, (1990) on seven patients who underwent a vertical hemilaryngectomy. Hirano, et. al., (1987) obtained objective assessments of phonatory activity on fifty four individuals who underwent the extended frontolateral laryngectomy technique. Normal speaking subjects were not used as controls in any of these studies. While the results of these studies showed individual differences to be evident, some of the objective measurements displayed general tendencies to be similar. In these three studies, aerodynamic measurements of maximum phonation times were shorter then normal average values and mean flow rates for sustained phonation were generally greater then normal average values reflecting glottic incompetence.

Hirano, et. al. (1987) noted that acoustical measurements for fundamental frequency range varied from subject to subject as well as the intensity range. In many of the cases the ability to regulate fundamental frequency and intensity range for phonation were limited. According to Hirano, et. al. (1987) these limitations can be "attributed to the lack of muscular control on one side of the larynx".

Blaugrund, et. al. (1984) divided the twenty subjects into three groups and reported fundamental frequency and frequency range according to the reconstructive surgical techniques. Hemilaryngectomees with arytenoidectomy

(N=10, all males) demonstrated a fundamental frequency range of 80 to 133 Hz with some individuals showing a limited frequency range of 80 to 81 Hz and others demonstrating a range of 80 to 280 Hz. Videostroboscopic examinations revealed that the remaining arytenoid moves anteriorly and medially to meet the epiglottis when voicing takes place. According to Blaugrund, et. al. (1984), normal speakers have a fundamental frequency of 120 Hz in men and 240 Hz in women with the frequency range being 60 to 500 Hz in men and 120 to 800 Hz in females.

Hemilaryngectomees without an arytenoidectomy (N=6, 3 males and 3 females) displayed a higher fundamental frequency, range 80 to 150 Hz, with a frequency range of, 80 to 280 Hz. Higher fundamental frequency measures 1 8 were those of the female subjects although this did not hold true for the frequency range measurements. The videostroboscopic examinations revealed that voicing was predominantly supraglottic with a glottic component.

Individuals who underwent an anterior commissure technique (N= 4, all males) showed a fundamental frequency range of 80 to 200 Hz and wider frequency range, 80 to 720 Hz. Videostroboscopic examinations revealed voicing to be produced by vibrations created through the action of the arytenoids and epiglottis.

During sustained phonation, Leeper, et. al. (1990) reported elevated mean fundamental frequency for the following vowels: /i/ = 191 Hz, range 79 - 274

Hz; /a/ = 168 Hz, range 60 - 241 Hz; and /u/ 207 Hz, range 71 - 300 Hz. The vocal fundamental frequency is thus greater than expected for adult males and the frequency range and variability is much larger than normal adult males (Baken,

1987). These measurements are also higher than those reported by Blaugrund, et. al. (1984).

Leeper, et. al. (1990) also measured the average intensity (in dBSPL) for the sustained vowels in the each speaker's modal pitch. The results are as follows: /i/ = 74, range 68 to 87 dBSPL; /a/ = 73, range 66 to 83 dBSPL; and /u/

= 76, range 67 to 84 dBSPL. The subjects were asked to attain their highest and lowest vocal intensity on the vowel /a/. The average intensity ranged from a low of 63 dB SPL to a high of 88 dB SPL. These intensity values according to

Leeper et. al. were within normal limits, however; the range and variation of the intensity values were reduced from the expected values for normal speakers

(Hirano, 1981).

A study by Rizer et. al. (1984) recorded nine subjects, three normal laryngeal speakers, three individuals who underwent conservation laryngeal surgery and three total laryngectomee speakers who used an artificial larynx.

All speakers were recorded in a quiet environment and read 50 monosyllabic words and the "Rainbow Passage" (Fairbanks, 1940). The words were then played to a "group" of listeners and the number of correct responses was converted to a percentage that became the intelligibility score. The "Rainbow

Passage" (Fairbanks, 1940) of each speaker was analyzed using the Voice

Identification, Inc., PM Voice Monitor 302 microcomputer and a Digital PDP-

11/34 computer. The acoustical values of fundamental frequency, jitter (the cycle to cycle variation of adjacent wave periods), voice-to-voiceless ratio (a ratio of the time spent phonating versus the time in silence), and words per minute (the speed of reading the passage) were correlated (Pearson's r) with the intelligibility scores from the monosyllabic words. They concluded that measures of duration and the number of words per minute correlated with intelligibility, i.e. faster speech rates yielded higher intelligibility scores. It was also noted that fundamental frequency did not contribute to intelligibility. Jitter was calculated for only the normal and conservation surgical group and was found to have a moderate correlation with intelligibility. These investigators also reported that those speakers who voiced a greater percentage of time were more intelligible. This study used a limited sample size and did not control for homogeneity. The generalizability of these findings are almost nil.

Additionally, this study analyzed two separate speaker samples, monosyllabic words for the intelligibility study and a paragraph reading for the acoustical study and used the results for direct comparison. 20 Summary

It is noted from this literature review that additional research is needed to explore the relationship between intelligibility and acoustical characteristics of

individuals who undergo conservation laryngeal surgery. This chapter has presented a definition of the vertical and horizontal hemilaryngectomy which

serves to preserve the voice of the individual. A majority of the studies of voice following conservation surgery of the larynx subjectively report voice quality.

In addition, very little is known about the speech and voice of the supraglottic laryngectomy speakers

The acoustical characteristics of hemilaryngectomy voice have focused on

the parameters of fundamental frequency, intensity range of phonation, and

aerodymanic measures of maximum phonation time and mean airflow rate.

Videostroboscopic examinations have also been conducted following a

hemilaryngectomy. These measurements were taken from sustained vowels. In

one study acoustical measurements were extracted from a reading passage which

included a standard hemilaryngectomee, a frontolateral hemilaryngectomee, and

a supraglottic laryngectomee. These results were then reported under one group.

To date, information regarding speech and voice of conservation laryngeal

surgeries have predominantly been subjective and qualitative. The objectives of

this researcher are twofold; (1) to find out if conservational laryngeal surgery via

hemilaryngectomy, supraglottic laryngectomy, by comparison to normal

laryngeal speakers produces a predictable effect on the intelligibility of speech,

and (2) to analyze the acoustic signal to determine what parameters predict

intelligibility. From the literature review the following decisions were made:

1. To have at least nine speakers per group (normal speakers, hemilaryngectomy, and supraglottic laryngectomy). Due to the variability of surgical procedures it was decided that at least nine subjects would be a representative sample for each surgical group.

2. To match the age of the normal speakers as closely to the ages of individuals in the two partial laryngectomy groups. Normal speakers serve as the control group and matching age is a mechanism that this investigator can use to increase the equivalence between the control group and the two investigational groups.

3. To use sentences from the Speech Perception In Noise Test (SPIN) instead of monosyllabic words for the speakers to read to play to a group of listeners. The SPIN sentences are selected to provide semantic contextual cues and provide for longer and more natural utterances.

4. To use a large group of naive listeners to participate in the perceptual part of the study so the results of this investigation can be generalized to a larger population.

5. To analyze the same speech stimuli from the speakers that individual listeners will hear. This assures a direct comparison of what the speakers say and what the listeners hear. The acoustic attributes are thus directly related to the intelligibility attributes. CHAPTER IH

METHODS

This study was designed to measure intelligibility and acoustical variables of speech in hemilaryngectomy and supraglottic laryngectomy speakers in comparison to normal laryngeal speakers. The procedures of this study were applied in order to obtain recorded speech samples from the three groups of speakers. Twenty seven speakers (9 per group) each read 40 selected sentences from the Speech Perception In Noise Test (Kalikow, Stevens, and Elliot, 1977).

These sentences contained high predictability and low predictability sentences and were recorded and subsequently presented under two conditions: no noise and 75 dB SPL or 75 dB A of white noise. (The discrepancy between SPL and

A scales is explained later). Thirty one listeners participated in the perceptual part of this study. The listeners were requested to write down the last word they heard in each of the 1,080 sentences for a total of 33,480 responses. The dependent variable was the number of correctly identified responses. The independent variables were: speaker type (hemilaryngectomy, supraglottic laryngectomy, and normal laryngeal speakers), noise condition (no noise and noise), and semantic contextual predictability (high and low).

The sentences of each speaker were acoustically analyzed to extract 12 continuous variables per sentence, totaling 12,960 data points. The acoustical

22 part of this study produced the following continuous independent variables: duration with its standard deviation of each sentence, key word, and vowel nucleus in the key word; mean fundamental frequency with its standard deviation of each sentence, key word, and vowel nucleus in the key word; percentage of voicing with its standard deviation of each sentence, key word, and vowel nucleus in the key word; and mean vocal intensity with its standard deviation of each sentence, key word, and vowel nucleus in the key word. Computational time to generate these acoustical variables was approximately thirty hours of actual computer time. It took pproximately 45 to 60 minutes per sentence to identify and mark the begining and ending of the sentence, key word, and vowel nucleus.

Speaking Subjects

A total of 27 male subjects supplied speech samples for this investigation.

Three groups of 9 participants per group were formed; normal laryngeal speakers, supraglottic laryngectomees and hemilaryngectomees. The Ohio State

University's Department of Otolaryngology and an Otolaryngologist in private practice from Columbus, Ohio, supplied the investigator with names of individuals who had undergone either a supraglottic laryngectomy or a hemilaryngectomy.

The normal laryngeal speakers were matched as closely as possible in age to the two surgical groups. The laryngeal speakers had no history of voice disorders. Ages,represented in years and months (yrsrmos), for the normal laryngeal speakers ranged from 39:11 years to 73:8 years, with a mean age of

59:4 years. Individuals who underwent a supraglottic laryngectomy ranged in 2 age from 43:0 years to 66:7 years , with a mean age of 56:3 years. The mean period of time since surgery for this group was 2:1 years, and ranged from 1 month to 8:8 years. Ages of the hemilaryngectomees ranged from 43:3 years to

78:11 years, with a mean age of 54:5 years. The mean period of time since surgery for this group was 3:1 years, and ranged from 2 months to 6:10 years.

At the time of recording, the hemilaryngectomees and supraglottic laryngectomees were free of cancer and remained disease free at least six months post recording at which time contact for the purposes of this study was terminated. Appendix A displays details for each speaker from which the above pooled data were obtained.

A bilateral hearing screening at 500Hz, 1000Hz, and 2000Hz (ANSI,

1969), was administered to each speaker prior to recording. Hearing tests were conducted within a sound treated booth (LAC, Model 401 ATR) and all subjects passed a hearing screening of 35dB HL or better in at least one ear (Hardick,

Melnick, Hawes, Pillion, Stephens, Perlmutter, 1980).

All speakers were native speakers of English who reportedly and by the judgment of the investigator had no history of articulation, stuttering, reading, or language problems.

Materials

Selection of Verbal Stimuli

All sentences (total of 400; 200 high predictability and 200 low predictability) from the Speech Perception in Noise Test (Kaliko, Stevens &

Elliot, 1977) were typed and stored on an AT&T computer. A program written in Turbo Pascal 4.0 was used to randomize these sentences into two groups. A total of 40 sentences were generated for each speaker: 50 % for high predictability and 50 % for low predictability. An example of a high predictability sentence is "The doctor prescribed the DRUG", and an example of a low predictability sentence is "We could consider the FEAST".

Generating The Noise Tape

White noise was recorded onto a high quality 0-02 audio tape (TDK)

SA90 high bias 70(is EQ. Output lines from a noise generator (Coulboum

Modules S81-02) were connected to the right and left input channels of a cassette deck (Technics, M235X). Headphones (Telephonies TDH-49p) were plugged into the cassette deck. The output of the noise signal was calibrated at 75 dB

SPL using an impluse precision sound level meter (Quest Electronics, Model

155) with associated artificial earphone coupler (Model EC-9A) and microphone

(Model AS-1550). The input level on the tape deck was adjusted to record at zero on the peak level meter and the left/right channels were balanced during the recording. No cassette filtering was used. The output of the noise generator was adjusted so the sound level meter read 75dB SPL. The sound level meter was set on linear and slow response. Each phone was calibrated and the noise recorded within +/- 1/2 dB SPL between the two phones.

Procedures

Calibration Procedures

All recordings were conducted within a sound treated audiometric booth

(IAC Model 402ATR) in the Department of Otolaryngology at The Ohio State

University. To insure subsequent accurate intensity measurements, a reference signal was recorded for ten seconds on the left channel prior to the speakers' 2 recordings. An electrolarynx (P.O. Vox Companion C 100) generated the reference signal which registered 71 dB SPL on a pulse precision sound level meter (Bruel &Kjaer Type 2203/1613) with a vibrating-surface-to microphone distance of 7.5 inches (19.05cm).

Recording Instrumentation

High-quality speech recordings were made of each speaker’s utterances using a stereo cassette deck (Nakamichi CR-2), power supply (Nakamichi PS

100), and a mixer (Nakamichi MX 100). Since this tape deck had only line input facilities and no direct microphone input, a separate microphone mixer with line-level outputs was used for recording. The microphone mixer required a separate power supply. The output of the power supply was connected to the input of the mixer and the output of the mixer to the tape deck's line input jacks.

A microphone (Sony ECM-170) was connected to the left channel input of the microphone mixer. High quality 0 0 2 audio cassettes (TDK SA90) were used for all recordings. Speech was recorded onto the left channel input of the microphone mixer MX-100 to the Nakamichi CR-2A cassette deck with a setting of SX(II) in, Eq switch in for 70 ps, Dolby C in, MPX filter off, and bias tune control set in the center position. The recording level for each speaker was set by adjusting the input level to read between 0 dB to +3 dB on the peak level meters (optimum recording using Q 02 tapes as recommended by Nakamichi in their owner's manual). This recording level was adjusted during the speaker's practice session for familiarization with the material. After the recording levels were set, the known reference level was recorded to tape. 27 Recording the Speakers

The investigator provided each subject with a "Consent to Investigational

Procedure" (Appendix B) which those participating in the study read and signed.

Instructions were given verbally and in writing. To familiarize the subjects with the test stimuli before recording, each subject read aloud the first paragraph of the "Rainbow Passage" (Fairbanks, 1960) and two sets of 20 randomized sentences from the Speech Perception in Noise Test. Once the subject was familiar with the speech stimuli, recording began. A microphone was mounted onto a microphone stand next to the seated subject. A string measuring 7.5 inches was secured around the microphone and held taut to measure mouth to microphone distance and reference signal to microphone distance for each subject recorded. The PO Vox was set at maximum gain and the battery was checked periodically to insure power output remained constant. Each subject read the stimuli in a no noise condition without headsets followed by a noise condition of 75dB SPL presented binaurally through headsets.

Playback of Noise

Under the noise condition, subjects heard 75dB SPL of white noise presented binaurally via TDH 49P (Telephonies 296 D 100-1) headsets.

Playback of noise was through the Technics, M235X tape deck with line output adjusted to the center for equal output to the headsets. Listening Task

Listeners

A total of 31 listeners, 12 males ranged in age from 18 to 29 years with a mean age of 23:6 years and 19 females ranged in age from 19 to 29 years with a mean age of 22:4 years, volunteered for this study. All listeners met the following criteria for acceptance; normal hearing, English as the native language, no familiarity with the speech of supraglottic laryngectomees and hemilaryngectomees, and inexperienced with psychophysical research.

Familiarity was defined as having a relative, close friend, or an associate who had a supraglottic or hemilaryngectomy. All listeners had peripheral auditory threshold sensitivity within normal limits. Thresholds were measured with a

Beltone Model 120 portable audiometer in a controlled acoustical environment

(IAC Model 402 ATR). Normal limits was defined as pure tone air thresholds of 20 dB HL or lower at octave intervals from 250 Hz to 8000 Hz (ANSI,

1969).

Generating The Listening Tapes

The analog signal of the 27 speakers stimuli (total of 1080 sentences), reference signal and the recording of the second and third sentences of the

"Rainbow Passage" (Fairbanks,1960) were digitized via an AT&T DSP32 analog-to-digital converter using the Sun-4/150 CXP Model 647, SunOS 4.0.3 microsystem computer and Entropic Signal Processing System (ESPS 3.3).

These recordings were made using an ultrawideband linear phase cassette deck

(Harmon/Kardon CD 491) and a high voltage/high current integrated amplifier

(Harmon/Kardon PM 640 Vxi) connected to the Sun-4/150. To hear playback of the signal a Boston Acoustics A40 Series II 80 HMS speaker was used. The 29 speech signal was sampled at 16 kHz with each sample being represented by 16 bits. The digitized speech signals were displayed and edited using Waves+, an interactive graphics program. Each speech file was edited to eliminate extraneous noise before and after the stimuli. A five second steady portion of the reference signal was edited and stored on the computer for each speaker.

This reference signal was of known intensity (71 dB SPL) for the microphone distance of 7.5 inches and was recorded at that distance before each speaker was recorded. Different speakers had different average loudness levels which required the investigator to adjust the recording level for each speaker while practicing reading aloud the first paragraph of the "Rainbow Passage"

(Fairbanks, 1960). Once the recording level was set the P. O. Vox signal was recorded and the levels remained unchanged during the recording session.

A software program was written by Professor Reiner Wilhelms in the

Speech and Hearing Science Division at The Ohio State University using C programing language and an ESPS subroutine library on the Sun-4/150 computer to generate a white noise background for playback of the sentences in the noise condition. This white noise had a level of 75 dB SPL during its steady state interval. The white noise was then mixed simultaneously with the speech signal in the noise conditions. The noise faded in before the test sentence and then faded out after the test sentence in order to avoid disturbance by sharp on and off sets. The details of the algorithm for generating the noise are described below.

The test signal recorded from the P. O. Vox was analyzed to obtain its root mean square (rms) value over a duration of 5 seconds. In all cases a sampling rate of 16kHz was used, so the rms value was estimated over Nr = 80,000 samples. The rms was evaluated by :

A pseudo-random number sequence was used as a noise source, which had the following properties. It was generated from a linear congruential algorithm based on a 48 bit integer arithmetic; therefore, the period length was much longer than the total duration of any used noise signal. The algorithm used to generate the next pseudo-random number X n+\ from the previous one, Xn, was: X/i+l = (flXn + c) mod m with the following constants in hexadecimal notation a = 5DEECE66D\^ and c =

B \$ , the modulus m w a s 2 ^ 8 . The distribution of the pseudo-random number sequence was in the interval (0,1), and transformed into the symmetric interval (- |) by subtracting The root mean square value of the noise was; therefore, integration over a uniform probability density function of constant value 1 over the interval ( - |):

Rn='\l -[i12ds = Vn

In order to obtain a noise of 75 dB SPL, the signal had to be multiplyed by a gain G. This was determined as follows. Since the rms value of the reference 3 1 signal was a known 71 dB SPL and P ref was the threshold of hearing sound pressure level (or some other reference level):

For the unknown gain G the noise source had to produce 75 dB SPL; therefore:

By combining the above equations and resolving for G, the following was obtained:

G = 1 - 10(4/20) = r x 5.49023

Since the recording level for the different speakers was adjusted individually, the widely varying (digital) rms values for the reference signals were computed, as shown in Table 1. For the generation of the output signals, a gain factor was used which corresponded to a reference rms value as computed from all references, see Table 1.

The noise source was switched on and off using slowly increasing and decreasing ramps to avoid any abrupt on and off sets for the listener. This noise ramp was generated by the following algorithm. If G represented the maximum gain of the noise source and N the duration of the ramp during which the noise 3 2 was increasing, then the actual gain was calculated at sample n, where n varies from 1 to N as:

and as

for the fading out noise. N was 10240 samples, corresponding to a ramp duration of 0.64 seconds. In addition, before the onset of the sentences and after each sentence the noise was held at a steady state for 10240 samples (0.64 secs.) before, and 8192 samples (0.512 secs.) after the sentence. The beginning and ending of the sentence are understood here as the beginning and ending of the edited sound files. Table 1. Computed Root Mean Squares for Reference Signals per Speaker

Speaker Type Signal RMS

Normal ref. 1 436.180 Normal ref. 2 505.281 Normal ref. 3 662.846 Normal ref. 4 1792.895 Normal ref. 5 1753.186 Normal ref. 6 670.696 Normal ref. 7 1032.677 Normal ref. 8 318.446 Normal ref. 9 777.346 Hemi ref. 1 921.802 Hemi ref. 2 890.226 Hemi ref. 3 1172.818 Hemi ref. 4 1598.266 Hemi ref. 5 1614.261 Hemi ref. 6 702.397 Hemi ref. 7 727.603 Hemi ref. 8 805.734 Hemi ref. 9 206.575 Supra ref. 1 363.517 Supra ref. 2 1035.275 Supra ref. 3 486.702 Supra ref. 4 716.178 Supra ref. 5 811.743 Supra ref. 6 1360.982 Supra ref. 7 720.135 Supra ref. 8 890.473 Supra ref. 9 1160.116 Total Means Square 985.252 34 Digital to analog listener tapes were created using the Sun 4/150 and the same equipment listed in the first paragraph under generating listening tapes in the listening task section of this chapter. The order of presentation of the 27 speakers per speaking condition was randomized to create 54 sets of speech stimuli. The listeners response forms in Appendix C displays the random order of presentation of the speakers per condition. Each set of speech stimuli consisted of either 10 high predictability and 10 low predictability or 9 high predictability and 11 low predictability or vice versa. To acquaint the listeners with the speaker's voice and speech, a representative sample of each speaker's voice consisting of the second and third sentence of the "Rainbow Passage"

(Fairbanks, 1960) preceded each speaker, regardless of the condition that followed.

In the noise condition, the second and third sentences of the "Rainbow

Passage" (Fairbanks, 1960) were followed by a 5 second pause and 3 seconds of 75 dB SPL of noise without speech and finally the 20 sentences mixed with

75 dB SPL of noise. The stimuli and noise were presented to both ears simultaneously. In both conditions there was a 15 second pause between speakers and a 4 second pause between sentences to allow enough time for the listener to write down the response

Presentation of the Speaker Tapes to Listeners

Each listener heard all 27 subjects in the no noise and noise conditions.

The investigator provided each listener with a "Consent to Investigational

Procedures" (Appendix D) which those participating in the study read and signed. The listeners were given response forms which provided written instructions, "Instructions for Listeners" (Appendix C) and response blanks for writing what they perceived as the last word in each sentence. Verbal instructions identical to the written instructions were also given by the investigator. The investigator provided a training session using 10 speech samples spoken by the investigator (5 high predictability and 5 low predictability sentences) to familiarize listeners with the task. The investigator presented the speech samples without visual cues. The listeners were encouraged to guess at the final word if they were uncertain or to place an X on the response form if they were unable to guess the word.

Procedure for the Listeners

The listeners were seated in a quiet classroom. The recordings of each speaker's utterances were played binaurally through headsets (TDH-50P). The output of the stereo cassette deck (Nakamichi CR-2) with settings of SX(II) in,

Eq switch in for 70 fis, Dolby C in, MPX filter off and bias tune control set in the center position, was connected to the input of the Harmon/Kardon stereo integrated amplifier PM645. The settings for the Harmon/Kardon amplifier were speaker 2 in, bass and treble minus, mode to mono, tape monitor to tape 1, function to tuner, and volume was set to register 75 dBA output. The left and right output of the Nakamichi cassette deck was connected to the left and right tape 1 input of the amplifier. A breakout box containing 8 headsets (TDH-50P) was wired to the left and right speaker system 2 of the Harmon/Kardon amplifier.

The output level was calibrated using the 75 dB SPL noise signal recorded on the listeners' tapes. The level was set with an acoustic coupler sound level meter (Bruel & Kjaer, Type 2209) using the A weighting filter. Initially the sound level meter was set on linear and slow response but due to the inability to sustain a steady reading the A weighting filter was used. This investigator confirmed the use of the A weighting filter with members of her committee.

These levels were set in an anechoic chamber and achieved by playing the recorded 75 dB SPL noise signal and adjusting the gain of the tape cassette. The gain of the amplifier was adjusted to reduce internal tape hiss. All settings were secured with tape to prevent the settings from accidently being turned. Periodic calibrations were taken throughout this data gathering phase to insure consist output levels. The listeners, therefore, received the noise signal at 75 dB A and the speech signals adjusted in intensity as a function of the adjustment of the noise signal.

Scoring of the Listener's Responses

Each listener's response was determined correct or incorrect by the investigator. The listeners' written responses (last word) were compared with the original list from which the sentences were read by each speaker. A written word was correct if it was spelled as a homonym. For example, the written word lute was counted correct as equivalent to the original word loot.

Misspelled words were evaluated in terms of the investigators opinion, such as brades was counted as correct for the original word braids. Pluralized written words were incorrect if the original word was singular or vice versa. For example, the written words drugs and bead were counted incorrect for the original words drug and beads respectively. This investigator chose to accept the key word that was read by the speaker which did not differ from the original list developed by Kalikow, et. al. (1977). 37 Reliability of Measurements

To be confident in the measurements of this study, reliability tests were performed. The following are the procedures and results used to assess reliability.

Reliability of Reference Tone and Noise Generated Signal

A +4 dB difference was measured by the sound level meter between the reference tone and the generated noise tape. In order to insure this +4 dB difference between the reference tone and the 75 dB SPL of white noise, generated on the Sun 4/150 computer for mixing with the sentences in the noise condition, a reliability test was performed. A program was written to select seven random reference tones recorded before each speaker (ref hemi 3, ref norm 4, ref supra 4, ref supra 7, ref norm 5, ref norm 9, ref supra 6). A test audio tape was created to record these reference tones and the computer generated white noise. The two signals were measured using a sound level meter Bruel and Kjaer Type 2203/1613, Harman/Kardon CD 491 cassette tape recorder and a Harmon/Kardon 640 Vxi amplifier. The difference between the signals was +4 dB with precision of measurement being plus or minus ^ dB as registered on the meter.

A Bruel and Kjaer Model 2305 graphic level recorder was utilized to measure tracings of amplitude of the original taped sentences and the reference tone. This showed a +4 dB difference. The computer generated white noise mixed with the sentences under the noise conditions and the reference tone also showed a +4 dB difference. This was referred to as +4 dB stimuli/noise ratio. 38 Acoustical Analyses

The digitized speech signal of each speaker's utterances was analyzed using the Entropic Signal Processing System (ESPS) and waves+, an interactive graphics program on the Sun 4. Waves+ also has a menu and mouse interaction. Spectral analysis techniques were used to obtain measurements of duration of the sentence, the last word in the sentence (key word) and the vowel nucleus in the key word. Both broad-band and narrow-band spectrograms were used to identify the the beginning and termination of the various segments.

Spectography permitted a visual presentation of the three dimensional acoustical structures of the speaker's utterance in frequency, intensity, and time

(Yanagihara, 1967). The waveform of each sentence was displayed on the computer screen. An advantage of using the waves+ program was that the entire sentence waveform, broad-band and narrow-band spectrograms were displayed simultaneously in time synchronous viewing using multiple windows to analyze the marked speech sample. The investigator marked the beginning and ending of the sentence using cursors. The investigator audibly playbacked the marked segment multiple times via a Boston Acoustics A 40 Series II80 HMS speaker.

Questionable marked segments were viewed using the zoom to increase the temporal resolution. Final marked segments were then stored in appropriate files and measurements were made within an accuracy of approximately .06 milliseconds (16 kHz).

There were 1,080 sentences of which both broad-band and narrow-band spectrograms were displayed and audibly played back. Both broad-band and narrow-band spectrograms were displayed for the key word and vowel nucleus.

Techniques described by Pickett (1980), Baken (1987), Isshiki, Yanaghihara and Morimoto (1966), Yanagihara (1967a,b) Lisker and Abramson (1967), 39 Halle, Hughes, and Radley (1957), Lehiste and Peterson (1961), Peterson and

Barney (1952), and Peterson and Lehiste (1960) were used to determine durational measurements. The investigator recorded the exact time of the beginning and ending of the marked segments to within an accuracy of approximately .06 milliseconds (16 kHz).

A software program was written by Professor Reiner Wilhelms in the

Speech and Hearing Science Division at The Ohio State University using ESPS on the Sun-4/150 computer to extract the following acoustical variables on the marked segments: RMS in dB SPL, duration in milliseconds, mean fundamental frequency, and percent of voicing of the marked sentence, key word, and vowel nucleus. There were 12 dependent variables that were measured which equalled

12,960 data points.

An algorithm which was implemented in a program called formant, a part of the ESPS software, was used to estimate the fundamental frequency of voiced sounds and for assessing voiced versus unvoiced segments. The program was used in a setting where it only makes voiced and unvoiced decisions and estimates the fundamental frequency at every 10 ms (frame duration) interval.

The algorithm is based on the following: First the signal is low-pass filtered and downsampled to 8 kHz, then the signal is high-pass filtered to remove low frequency rumble with a cut-off of approximately 80 Hz. Preemphasis is applied with a preemphasis coefficient of 0.7, and then a set of 12^ order linear predictive coding (LPC) coefficients are estimated based on a signal portion of

49 ms duration multiplied with a cos 4 window. This LPC filter is used as inverse filter to remove part of the vocal tract characteristics from the signal. The estimation of the fundamental frequency is based on calculating the autoconrelation function of the inverse filtered signal. A dynamic programming 40 strategy is used to track the fundamental frequency. The program computes a voicing likelihood value, which is close to 1 for voiced and close to 0 for unvoiced speech in general. The program formant was used with its standard settings of parameters, as are usually used for (normal) male speakers. The files generated by the program were evaluated with a special software which extracts the voiced and unvoiced information, the fundamental frequency, and the rms values for marked sentences, words, and vowel nuclei frame by frame from the output files generated by the program formant.

Reliability in the Segmentation of the Acoustical Stimuli

The critical component of the acoustical analysis was the segmentation of each individual speakers' utterances. The three segments (sentence length, key word, and vowel nucleus of the key word) were defined by five markings: sentence onset, key word onset, sentence termination (which marked both sentence and key word terminal boundary), and vowel onset and termination in the key word. Not only did this segmentation process measure the durational measures for each sentence, but also identified for the acoustical analysis software system the segments for analysis, thereby providing the remaining twelve dependent variables. The replication of the segmentation, therefore, was critical to establishing the reliability of the acoustical analysis procedures of this investigation.

To test this reliability, 35 utterances were selected for segmentation by an individual independent from this investigation and unaware of the results of the investigator's segmentation. Since the present study was conducted to investigate the nature of dysphonic speech, the 35 sentences selected for re segmentation were the 35 sentences with the lowest percentage of voicing in the 41 vowel nucleus of the key word. In the vowels of normal speakers the

percentage of voicing should approximate 100%; therefore, reduction in this proportion should be associated with dysphonia and with the presence of noise

in the speech signal. Such conditions create the potential for more subjective interpretation of the utterances' waveforms and sonograms, thereby reducing

inter-judge reliability.

The second judge was provided with the procedures used for segmentation

(found in Chapter 3) and trained in the use of the Sun SPARC workstation by

Professors Wilhelms and Trudeau. To determine the degree to which the two investigators concurred in marking the initiation and termination of the sentence, final word and vowel nucleus of the final word, the data sets from the two investigators were analyzed in the following fashion.

1. Absolute mean differences were calculated for the cursor markings of the initiation and termination of the entire sentence. These marks should have been the ones with the greatest inteijudge reliability as the acoustic information before and after the sentence should have been either no signal or nonspeech.

Trained judges should have no difficulties in identifying either. The absolute mean difference between investigators for the initiation of the sentence was

0.0245 secs.and for the termination of the sentence it was 0.0459 secs. For the overall duration of the token R = .986 (R^ = .973. From this analysis, it was evident that both investigators concurred concerning when speech began.

Based on this concurrence the remaining correlations were determined since any deviation between the judges would have to be represented as differences in the amount of signal (in ms.) to have occurred between the 42 initiation of the signal and the beginning or end of the segment in question (final word or vowel nucleus).

2. Proceeding through the token, the next segmentation was the initiation of the final word. In measuring from the initiation of the token the correlation between the two investigators was R = .995, with an average absolute difference of 33.6 ms.

3. Proceeding through the token, the next segmentation was the initiation of the vowel nucleus in the final word. In measuring from the initiation of the token the correlation between the two investigators was R = .992, with an average absolute difference of 43.0 ms.

4. Proceeding through the token, the next segmentation was the termination of the vowel nucleus in the final word. In measuring from the initiation of the token the correlation between the two investigators was R =

.967, with an average absolute difference of 82.1 ms.

The results of these correlations indicate that the method of segmentation employed in this study (i.e., the simultaneous time synchronous viewing of wide-band spectrograms, narrow-band spectrograms, waveforms, and auditory review) was highly reliable even for dysphonic speech signals.

Acoustic Onsets and Offsets of Marking the Sentence, Key Word, and Vowel Nucleus

The waves+ software program made it possible to align the cursors in real time and mark the beginning and ending of the sentence, key word, and vowel nucleus and at the same time visually study the waveform, broad band and narrow band spectrograms. The end of the key word was also the end of the sentence. An audio playback of the signal allowed this investigator to hear the 43 selected signal monitor display. A zoom capability was occasionally used to magnify a selected portion of the signal to aid in marking the segments.

Sentences

The onset of the sentence was detected at the point in time where the amplitude in the waveform increased above the intrinsic noise level of the file signal recorded during the silent period prior to the initiation of speech.

Appendix H displays the marked sentence "Paul wants to speak about the bugs".

The dotted vertical lines show the beginning and ending of the sentence. The reader is cautioned that the screen printouts do not depict the high resolution that is visible on the display monitor.

The offset of the sentence paralleled the onset of the sentence in that termination was the absence of acoustic energy detected where the amplitude of the waveform was above the intrinsic noise level before the silent period at the end of the sentence. Termination was also reinforced when no identifiable speech signal was visually seen in the waveform, broad band or narrow band spectrograms and when no speech signal was audibly heard.

Key Word

If a word began with a fricative, the cursor was placed where the strong continuous spectrum component or noise turbulence initiated. If a word began with a stop consonant the cursor was placed at the beginning of the silent closure period for an unvoiced stop and at the beginning of the the vertical striations for a voiced stop. The findings of Pickett (1980) were employed: 4 "The stop or plosive consonants [p, t, k, b, d, g] are produced by a movement that completely occludes the vocal tract. During the occlusion there is either complete silence or only weak, low frequency sound. There is a complete silence for an unvoiced stop; during the occlusion of a voiced stop there is only the sound of the very lowest harmonics as long as voicing is maintained during the occlusion. When the occlusion of a stop consonant is released to form a following vowel, a transient and, for unvoiced stops, a burst of noise-like sound occur during the release. Thus, in contrast to the continuous, strong, voiced sound of vowels, the stop consonants have an interval that is silent, or nearly so, followed by a release burst of sound." (p. 105)

The cursor was placed at the beginning of the nasal murmur (a low- intensity segment with a low-frequency band of energy) when the key word started with a nasal consonant. If the key word began with a glide the cursor was placed on the initial low frequency band of energy of the formant transition.

Appendix I displays the cursor markings (vertical dotted lines) of the beginning and ending of the key word "bugs" from the sentence "Paul wants to speak about the bugs."

Vowel Nucleus

Each vowel nucleus was initially identified marking the formant steady state which was determined by the spectrogram striations of visible glottal pulses and visible amplitudes of the first and second formant frequencies. An example of a marked vowel nucleus is seen in Appendix J. The vertical dotted lines depict the cursor markings of the beginning and ending of the vowel / / in the word bugs from the sentence "Paul wants to speak about the bugs."

A vowel following a voiceless stop consonant and a voiceless fricative was initially marked where dark vertical striations were readily visible at the onset of voicing in the first formant frequency following the aspirated burst from the plosive. The vowel following a voiced stop consonant and a voiced fricative was initially marked where there was increase in amplitude in the waveform and 45 in the case of fricative termination of fricated noise. The end of the vowel was marked on the last glottal pulse or visible vertical striation preceding silence if the word ended in a voiceless stop or voiceless fricative and marked at the beginning of the formant transition if the word ended in a voiced stop or voiced fricative or in the case of a voiced fricative the termination of the vowel occurred at the initiation of fricated noise.

For glides and nasals which either preceded or followed the vowel, the steady state of the vowel was identified by viewing the waveform and spectrograms. The investigator then moved the cursors, usually one glottal pulse at a time, to find the formant transitions. Auditory playback was important in segmenting the final steady state of the vowel in these words.

Diphthongs in words were segmented by marking the onglide and offglide when viewing the amplitude and first and second formant frequencies of the spectrogram. Cursors were moved to find and segment out the formant transitions as the investigator relied on auditory playback to determine the final marked steady state interval.

Statistical Analyses

The listener data was hand coded by the investigator. Machine ready datasets were prepared by double entry (two individuals entered the same data) and compared to minimize error. The double entry was transferred to the SUN system. A C-shell program compared the two datasets on number of blocks and number of columns per block. Another program flagged differences on data entries between the two datasets. Entry errors were corrected using a line editor.

The computer corrected version was then compared to the raw data coded by the investigator. The dependent variable in this investigation was whether the listener correctly identified the key word (last word) in each sentence. The outcome variable was binary, taking on the value of 1 for correctly identified key words or 0 for incorrectly identified words. Stepwise logistic regression using

BMDPLR (BMDP Statistical Software, Inc., 1990) was used on the IBM 3081 computer at The Ohio State University. This was the most effective means to screen a large number of variables and simultaneously fit a number of logistic regression equations (Neter, Wasserman and Kutner, 1988). The independent variables were categorical and in this investigation included between groups factor of speaker type (normal, hemilaryngectomy, supraglottic laryngectomy), and within groups factors of type of stimuli (high predictability verses low predictability) and condition (noise versus no noise). CHAPTER IV

RESULTS AND DISCUSSION

The present investigation was designed to evaluate the effects on intelligibility of vertical partial laryngectomy and horizontal partial laryngectomy.

The results of the statistical analysis of the data and interpretation of the results regarding the research questions for the intelligibility of these speakers in comparison to normal laryngeal speakers are presented in the first section of this chapter, followed by the results regarding the research questions for the acoustical characteristics of the speakers and finally the results and discussion of the acoustical variables which influenced intelligibility.

Descriptive Statistics of Intelligibility

Descriptive statistics (the mean percent correct and the standard deviations) were obtained on each speaker type by the experimental conditions of context predictability and competing noise. The following percentages and standard deviations are simply the calculated values taken from the actual number of correct and incorrect responses from the listeners' reponses for each sentence.

These results are reported to give the reader a general knowledge of patterns that 48 emerged from the intelligibility raw scores; however, the reader is cautioned that the statistical analysis used the log odds which will follow later in this chapter.

The main effect is presented initially followed by the speaker type by context predictability, speaker type by competing noise, and then speaker type by context predictability by competing noise results.

Group Means by Speaker Type

The cell means and standard deviation for this interaction are displayed in

Table 2.

Table 2. Intelligibility as a percentage of correctly identifying the final words (MeanNStd. Dev.) as a function of speaker type.

Speaker Type MeanNStd. Dev.

Normal 79.5N28.7 Supraglottic 66.4N34.6 Hemilaryngectomy 64.3N38.1

The overall intelligibility for normal speakers was 13 - 15% greater than for the two post-surgical groups. A 2% difference was noted between the two post- surgical groups with the supraglottic speakers being slightly higher than the hemilaryngectomy speakers. As would be expected from the binomial distribution, the standard deviations are higher for the groups with means closer to fifty percent. In general, the normal speakers were perceived as the most intelligible and the two post surgical speaker groups were perceived as being almost equally intelligible. 49 Group Means by Speaker Type and Context Predictability

The cell means and standard deviation for this interaction are displayed in

Table 3.

Table 3. Intelligibility as a percentage of correctly identifying the final words (MeanXStd.Dev.) among speaker types as a function of context predictability.

Context Predictability

High Low Predictability Predictability

Speaker Type MeanNStd. Dev. MeanNStd. Dev.

Normal 95.4X09.3 63.7X32.4 Supraglottic 81.5X24.8 52.0X36.4 Hemilaryngectomy 76.1X33.6 53.0X38.9

Within this condition intelligibility should be highest under high predictability when semantic contextual cues were present. It is evident from this table that the lack of semantic contextual cues do effect intelligibility in all speakers. In the absence of semantic contextual cues, the normal speakers had a reduction of intelligibility by 32 %, the supraglottic speakers by 30%, and the hemilaryngectomy speakers by 23%. As a group, the normal speakers were the most intelligible with little speaker variability under the high predictability condition. The mean intelligibility score for the normal speakers with use of semantic contextual cues was 14% to 19% higher when compared to the post surgical groups. When semantic contextual cues were given, the post surgical groups' mean intelligibility was similar as well as speaker variability under this condition. In the absence of semantic contextual cues, the normal speaker group was 11% higher in mean intelligibility as compared to the post surgical groups, however, the two post surgical groups were essentially equal in mean intelligibility as was exhibited by only a .9% difference between the two groups.

All speaker groups under the low predictability condition exhibited similar group variability within each group.

In general, all speaker groups were more intelligible when semantic contextual cues were given. The normal speakers were the most intelligible under both high and low predictability conditions. The two post surgical groups performed essentially the same when semantic contextual cues were given and again performance was similar between the two groups in the absence of semantic contextual cues. With the exception of the normal speakers under high predictability, all speaker groups showed similar speaker variability regardless of the condition. 5 1 Group Means by Speaker Type and Competing Noise

The cell means and standard deviations for this interaction are displayed in

Table 4.

Table 4. Intelligibility as a percentage of correctly identifying the final words (MeanNStd. Dev.) among speaker types as a function of competing noise.

Noise Condition

- Noise + Noise

Speaker Type (MeanNStd. Dev.) (MeanNStd. Dev.)

Normal 85.7N23.7 73.3N31.8 Supraglottic 82.8N26.4 50.1N34.1 Hemilaryngectomy 82.9N25.6 45.8N39.6

In the absence of noise all three speaker groups performed essentially equally in intelligibility. The addition of competing noise reduced the intelligibility of normal speakers by 12% and by 33 and 37% for the supraglottic and hemilaryngectomy speakers respectively. The normal speakers preserved intelligibility better in the noise condition as compared to the post surgical groups; however, there was little difference between the two post surgical groups in the noise condition. Variability among speakers in each group was essentially the same under the no noise condition. Although speaker variability was evident in each speaker group when noise was present, the hemilaryngectomy speaker group displayed the greatest variability.

In general, the mean intelligibility was reduced for all speaker groups in the presence of competing noise with reduction of at least 30% for the two post surgical speaker groups. The performance of the hemilaryngectomy speaker group under the competing noise condition exhibited the greatest variability in comparison to the supraglottic laryngectomy speaker group. The mean intelligibility was similar for all speaker groups with similar speaker group variability under the no noise condition.

Group Means by Speaker Type, Context Predictability, and Competing Noise

Group mean intelligibility data is displayed in Table 5 and reported by speaker type as a function of context predictability and competing noise.

Table 5. Intelligibility as a percentage of correctly identifying the final words (MeanNStd. Dev.) among speaker types as a function of context predictability and competing noise.

High Predictability Low Predictability Speaker - Noise + Noise - Noise + Noise Type (MeanNSD) (MeanNSD) (MeanNSD) (MeanNSD)

Normal 97.6N04.0 93.3N12.1 74.2N28.6 52.8N32.6

SupragloL 95.3N10.0 68.6N27.5 71.2N31.1 31.2N29.7

Hemilaryn. 94.4N10.7 58.7N38.4 72.4N30.3 32.6N36.5

All three speaker groups exhibited a reduction of intelligibility as a function of whether the final word was of high or low predictability. This pattern also emerged as a function of intelligibility in competing noise. In the absence of competing noise and when semantic contextual cues were given, the three 53 speaker groups intelligibility means were essentially similar. The absence of competing noise and the presence of semantic contextual cues was the most ideal condition to perceive the final word in the sentence as being correct. The greatest percentage difference was that of 3% which occurred between the normal speaker group and the hemilaryngectomy speaker group. In Appendix

E, Tables 47, 48, and 49 display the mean and standard deviation for each individual speaker per group under different conditions of competing noise and context predictability. Under no noise and when semantic contextual cues were given, Table 47 showed that the normal speakers’ mean intelligibility scores ranged from 93.6% to 99.7% correct, Table 48 showed the mean scores ranging from 83.9% to 99.0% correct for the hemilaryngectomy speakers, and Table 49 showed the mean scores ranging from 86.5% to 99.6% correct for the supraglottic laryngectomy speakers. There was little intra-speaker group variability among the normal speakers (range 1.0% to 8.7%) in the no noise high predictability condition; whereas, greater intra-speaker group variability was evident for the two post surgical groups (hemilaryngectomy range 1.6% to

20.8%, supraglottic range 1.1% to 17.9%).

All three speaker groups exhibited similar means in intelligibility under no noise and when no semantic contextual cues were given. Under these conditions, the normal speaker group in Table 47, Appendix E showed a range from 52.6% to 97.7% correct, the hemilaryngectomy speaker group in Table 48 showed a range from 35.8% to 90.0% correct, and the supraglottic laryngectomy speaker group in Table 49 showed a range from 47.4% to 88.3% correct. Even though intra-speaker group variability appears to be similar among all speaker groups under the no noise low predictability condition, the normal speaker group seem to display the greatest range of intra-speaker group variability (4.0% to 37.7% correct) as shown in Appendix E, Table 47. The hemilaryngectomy intra-speaker group variability ranged from 18.6% to 38.0% as shown in Table 48, and the supraglottic intra-speaker group variability ranged from 15.0% to 40.6% as shown in Table 49 in Appendix E.

Under the presence of competing noise and when semantic contextual cues were given, the normal speaker group displayed mean intelligibility scores that were 24 to 34% higher than the supraglottic and hemilaryngectomy speaker groups, respectively. Under these conditions, the competing noise seemed to have a greater effect on intelligibility for the hemilaryngectomy speaker group.

By examining the speaker group differences in Appendix E, Table 47 shows that the mean intelligibility scores for the normal speaker group ranged from 79.4% to 98.7% with intra-speaker group variability ranging from 1.7% to 21.8%.

Under the same conditions, Table 48 in Appendix E shows that the hemilaryngectomy speaker group have a larger range from 3.9% to 91.6% in mean intelligibility scores with intra-speaker group variability ranging from

8.5% to 35.3%. Table 49 in Appendix E, under the same conditions, showed that the supraglottic speaker group ranged from 47.1% to 94.2% in mean intelligibility with intra-speaker group variability ranging from 9.7% to 31.7%.

Between the two post surgical speaker groups, the hemilaryngectomy speaker group displayed the most intra-speaker variability

When competing noise was present and no semantic contextual cues were given, the normal speaker group was at least 20% more intelligible than the two post surgical speaker groups. Looking at Appendix E, the range for the normal speaker group in Table 47 was from 36.8% to 67.4%, for the hemilaryngectomy speaker group in Table 48 it was 2.1% to 73.9%, and for the supraglottic laryngectomy speaker group in Table 49 it was 13.0% to 50.0%. Competing noise under the low predictability condition seemed to greatly effect the post surgical speaker groups equally. Although looking at Table 48 in Appendix E, the variability among the hemilaryngectomy speaker group presented a slightly wider range (4.2% to 38.0%) in comparison to the supraglottic speaker group in

Table 49 (12.0% to 38.7%). This showed that the most and least intelligible speakers were within the hemilaryngectomy speaker group .

Overall means collapsed over speaker groups are not presented since evidence from the previously reported data showed differences between the normal speaker group and the two post surgical speaker groups.

Summary

The foregoing descriptive statistics regarding intelligibility revealed certain trends:

1. The normal speaker group displayed the highest mean intelligibility scores in comparison the pooled two post surgical speaker groups regardless of noise or context predictability conditions.

2. It was evident that competing noise decreased intelligibility for all three speaker groups regardless of contextual predictability. All speaker groups performed equally in the no noise condition.

3. The lack of semantic contextual cues affected the intelligibility in all speaker groups. The normal speaker group displayed greater intelligibility with less intra-speaker variability in comparison to the two post surgical speakers groups when semantic contextual cues were given and when no semantic cues were given.

4. Intelligibility scores were the highest and essentially equal for all three speaker groups in the no noise condition and when semantic contextual cues were given. Although intelligibility scores were generally lower in the no noise condition when no semantic contextual cues were given, all three speaker groups performed essentially equally. With competing noise present and semantic contextual cues given, the normal speaker group fared better than the two post surgical speaker groups. Under this condition, the hemilaryngectomy speaker group was greatly affected. All speaker groups were affected when competing noise was introduced and when no semantic contextual cues were given. In this condition the intelligibility scores were higher for the normal speaker group in comparison to the post surgical speaker group, although the post surgical speaker groups exhibited similar intelligibility scores.

The observed intelligibility and standard deviation scores above were the result of 31 listeners listening to all 1,080 sentences and correctly identifying the last word in each sentence. To examine the above trends further, a logistic regression statistical analysis was performed to investigate the potential relationship between the probability of the listeners perceiving the final word as correct under two conditions of noise and under two conditions of contextual predictability. A full explanation of this analysis will follow.

Logistic Regression

A logistic regression statistical model using BMDPLR (BMDP Statistical

Software, Inc. 1990) was used to analyze the perceptual data obtained from the listeners. Logistic regression is a way of describing the relationship between a dichotomous response variable, which refers to the listener's correct/incorrect responses in this study, and one or more explanatory variables. The model attempts to explain variations in the log odds of correctly identifying the key word for the levels of the independent variables. The independent variables (or 57 explanatory variables) of interest in the perceptual part of this study included speaker type (coded as 0 for normals, 1 for hemilaryngectomees, and 2 for supraglottic laryngectomees), context predictability (coded 1 for high predictability and 0 for low predictability), and noise condition (coded 0 for no noise and 1 for noise). The independent variable of listener was also included which will be explained later in this chapter.

Logistic regression was the most appropriate statistical model to use in this study for the following reasons. The descriptive statistics of means and standard deviations as displayed above do not control for listener effects. The means and standard deviations are also not directly relevant to other investigators because the experimental design has two competing noise conditions and two contextual conditions. Other investigators would have to run the exact experimental conditions to be able to obtain the same percentages correct and the same standard deviations. A more meaningful statistic is knowing how much the log odds would change when comparing normal speakers to hemilaryngectomy speakers to supraglottic laryngectomy speakers in some other set of circumstances. Logistic regression was the most appropriate model for testing the hypotheses since it controlled for all the listener's effects and the other explanatory variables (Hosmer and Lemeshow, 1989).

In logistic regression, the predicted proportion of success follows the estimate log odds of being correct:

i rvtH - l"i ( Probability of correct °g s - L °S \ probability of incorrect

In terms of selecting the most appropriate model, the independent variables namely, speaker type, competing noise condition, contextual predictability, and listeners with their interactions were included in the initial design matrix. 58 Several models were run using the approximate asymptotic covariance estimate

(ACE) (BMDP Statistical Software, Inc. 1990) to check for different patterns that emerged and to screen out any independent variables and interactions that were not important in the prediction of the outcome variable. A model with no interaction terms implied that each of the independent variables affected the response independently of the other independent variables, thus interactions that did not fit a model were subsequently removed due to the goodness of fit criteria.

The summary results of a stepwise regression procedure are shown in

Table. 6 which lists the models, degrees of freedom, log-likelihood, improved

X2 statistic, goodness-of-fit X2 statistic, and p values. The results show that the main effects of speaker type, noise condition, individual listener, and context predictability as being important in predicting intelligibility to be retained. Also interactions of speaker type by condition, speaker type by predictability, condition by predictability, and listener by condition showed sufficient evidence in predicting intelligibility. Adding listener by condition interaction was the best fit because listener by predictability or speaker type by condition by predictability did not improve the log-likelihood to the degree that these interactions should be included in the model. 59 Table 6. Summary of logistic regression models including degrees of fireedom, log likelihood, improvement in Chi-square, goodness of fit Chi-square, and p-values statistics of either entering or removing terms from the model.

Log Improvement Goodness of Fit Term df Likelihood Chi-Square />-Value Chi-Square p-Value

PREDIC 1 -18731.45 3330.39 0.000 6076.09 0.000 COND 1 -16888.48 3685.92 0.000 2390.26 0.000 SPTYPE 2 -16421.34 934.29 0.000 1455.84 0.000 S * C 2 -16262.86 316.95 0.000 1138.97 0.000 LISNUM 30 -16096.91 331.90 0.000 806.99 0.000 S * P 2 -15969.20 255.42 0.000 551.59 0.000 C * P 1 -15931.08 76.24 0.000 475.33 0.000 L * C 30 -15859.52 143.13 0.000 332.23 0.112 L * P 30 -15820.43 78.18 0.000 254.10 0.775 S * C * P 2 -15815.26 10.34 0.006 243.75 0.873

Determined by the initial design matrix above, the model that produced the

best fit was:

aaaa a aa a aa g = Po + P lc + P21sl + P22s2 + P3P + P41csl + P42cs2 + P5CP + P 61 PS1 + A A P62PS2 + P'n A were g represents the estimated log of the odds or logit, s represents speaker

type, c represents competing noise condition, p represents contextual

predictability, n is the vector notation for the thirty variables associated with

listener number.

This model of listener by condition, condition by predictability, speaker

type by predictability, and speaker type by condition was re-run using the

maximum likelihood ratio (MLR) (BMDP Statistical Software, Inc. 1990). The results of the model are shown in Table. 7 which lists the log-likelihood,

goodness-of-fit X2 statistic, degrees of freedom, and p values. The extraneous 60 variable regarding listeners had to be included in the model to test for significance of listener effect or any listener interaction effects with the explanatory variables of interest Listeners were randomly selected and screened with respect to major effects of listeners such as normal hearing,

English as their primary language, etc. and not selected in regards to homogeneous skills. This investigation was not designed to identify perceptual patterns arising due to intra-listener differences. An explanation of differences in the perception of intelligibility is; therefore, beyond the scope of this study.

The logistic regression model was fit to the listener by condition data using the dependent variable of identifying the key word correctly. The model indicates that the variable noise condition had a significant effect on the listener's ability to correctly identify the key word. The log odds ratios

Table 7. Log-Likelihood, Chi-Square, Degrees of Freedom (df) , and p- Values for the Final Model using logistic regression.

Log Goodness of Fit Goodness of Fit Likelihood Chi-Square Chi-Square (2*0*LN (0/E)) df p-Value (Hosmer-Lemeshow) df p-Value

-15859.52 332.23 302 0.112 14.93 8 0.061

(coefficient/standard error) indicate that some listeners did moderately well under the competing noise condition or had higher odds while others displayed much lower odds for correctly identifying the key word. Some listeners did well in both conditions and other listeners did poorly in both conditions. Since each individual listener heard all of the sentences that were produced by each speaker the performance seemed to be a matter of individual listener differences. The data gathered from the listeners including gender, age and hearing thresholds

(best ear and poorest ear) were analyzed to determine if the listeners differed in any way to account for listener variability. A one-way analysis of variance showed no differences among listeners as a function of gender, [F (1, 30) =

.001, p = .976]. No significant correlations were evident between hearing thresholds in either the best ear, Pearson r of .052 (df = 30) or poorest ear,

Pearson r of .134 (df = 30) and intelligibility, or between age, Pearson r of .083

(df = 30) and intelligibility.

The estimated odds, confidence intervals and the corresponding percentage for each speaker type for the four possible combinations of the values of noise condition and context predictability are shown in Tables 8,9, and 10.

Confidence interval levels were calculated using the covariance matrices for the log odds of the estimated parameters (Agresti, 1990) of speaker type, condition, predictability, speaker by condition, speaker by predictability, and the constant.

With 95% confidence this investigator can predict that the population odds fall within a set interval. 62

Table 8. Estimated odds and 95% Cl for the four possible combinations of variables noise condition and context predictability for normal speakers. Conversion of the odds into percentages is also displayed.

Noise Condition

Context Predictability No Noise Noise High Predictability 56.95\98% 16.33X94% (47.94, 67.64)\98-99% (14.28,18.67)X93-95% Low Predictability 3.40X77% .98X49% (03.12, 03.71)\76-79% (00.90,01.06)M7-51%

Table 9. Estimated odds and 95% Cl for the four possible combinations of variables noise condition and context predictability for supraglottic laryngectomy speakers Conversion of the odds into percentages is also displayed.

Noise Condition

Context Predictability No Noise Noise High Predictability 20.40X95% 2.59X72% (17.98, 23.14)X95-96% (2.40, 2.80)\71-74%

Low Predictability 03.02X75% 0.38X28% (02.79, 03.26)\74-77% (0.35, 0.41)X26-29% 63

Table 10. Estimated odds and 95% Cl for the four possible combinations of variables noise condition and context predictability for hemilaryngectomy speakers. Conversion of the odds into percentages is also displayed.

Noise Condition

Context Predictability No Noise Noise High Predictability 14.25\93% 1.72S63% (12.69, 15.99)\93,94% (1.60, 1.85)\61,65%

Low Predictability 3.26Y77% 0.39S28% (03.01, 03.52)\75,78% (0.36, 0.42)\27,30%

Tables 8,9 and 10 exhibit the estimated odds, 95% confidence interval levels, and the corresponding percentages for the four possible combinations of variables noise condition and context predictability for the normal speaker group, supraglottic laryngectomy speaker group, and hemilaryngectomy speaker group, respectively. The percentages listed in Tables 8,9, and 10 are not the same percentages listed in the raw data part of this chapter. These percentages are figured from the estimated log odds of correctly identifying the key word in the sentences; therefore, representing more generalizable trends for populations of normal, supraglottic, and hemilaryngectomy speakers.

This investigator will be talking about all three speaker groups and referring to Tables 8,9 and 10 in terms of the estimated odd for the four possible combinations of variables involving noise condition and context predictability.

For all speaker groups it was not surprising to note that the estimated odds was the highest when listeners were given semantic contextual cues under the no noise condition since tins would be the most ideal setting, i.e. giving the most information to a listener with the least amount of competing background noise.

Under this condition the estimated odds increases for the normal speaker group followed by the supraglottic laryngectomy speaker group and then the hemilaryngectomy speaker group. The term increases refers to the likelihood of the listener getting the final word in the sentence correct; therefore, the listener would have better odds in getting the final word correct in the most ideal setting

(no noise with the presence of semantic contextual cues) first for the normal speakers, then the supraglottic laryngectomy speakers and lastly the hemilaryngectomy speakers.

The normal speaker group did better under the presence of noise and when semantic contextual cues were given in comparison to the two post surgical groups as shown in Tables 8, 9, and 10.

It is evident from Tables 8, 9, and 10 that the combination of competing noise and no semantic contextual cues decreases the odds for all speaker types.

This condition greatly effected the intelligibility of the two post surgical groups.

The odds for the two post surgical groups, Tables 9 and 10, were similar in the absence of noise and when no semantic contextual cues were given. This suggest that the absence of competing noise was a factor in identifying the key word in the sentence for the post surgical groups even though no semantic contextual cues were given.

The post surgical groups demonstrated a decrease in the estimated odds,

Tables 9 and 10, in the presence of competing noise and when semantic contextual cues were given. This suggest that the presence of semantic contextual cues aided the listeners when competing noise was present to help correctly identifying the key word in the sentence. 65 Summary

A summary of the estimated odds in the above Tables 8,9, and 10 will follow. It can be concluded that overall odds of correctly identifying the last word for the two post-surgery speaker groups were generally lower in comparison to the odds for the normal speaker group. All three speaker groups exhibited a reduction in the estimated odds of intelligibility when the final word was of low predictability versus high predictability. This pattern also emerged as a function of intelligibility in competing noise.

For the normal speakers, the estimated odds of intelligibility was better preserved regardless of the noise condition and semantic contextual cues as compared to the post surgical groups. The results showed that listeners would have essentially the same odds of correctly identifying the last word in the sentence for supraglottic laryngectomy and hemilaryngectomy speakers when no semantic contextual cues are given under no noise, i. e., in the conditions most facilitative of intelligibility the three groups were equally intelligible. The results also showed that listeners would have essentially the same odds of correctly identifying the last word in the sentence for the two post surgical groups in the presence of competing noise and when no semantic contextual cues were given.

This completes the perceptual part of this investigation and now the focus will turn to the acoustical analyses of all 1,080 sentences that each speaker read and that each listener heard. 66 Descriptive Statistics of Acoustic Measures

Acoustical analyses of every sentence that each speaker produced were performed to yield objective data for the acoustic parameters of intensity, duration, fundamental frequency (FO), and voicing. A total of 12 parameters were measured and the descriptive statistics were computed for all of the continuous variables.

Intensity

The means and standard deviations of intensity of the sentence, key word, and vowel nucleus as a function of context predictability and noise condition are displayed in Table 11 The overall means of intensity measurements are higher under the noise condition for both high predictability and low predictability conditions. The intensity levels for the sentence, key word, and vowel nucleus were essentially equal when comparing the three speaker types in the high predictability no noise condition with the low predictability no noise condition.

The same pattern is present when comparing the three speaker types in the noise/high predictability condition with the noise/low predictability condition.

The intensity measures for the sentence and vowel nucleus were higher and similar in intensity in comparison to the key word for each speaker group regardless of the noise condition and predictability. The reason that all vowels would show a slightly higher intensity measurement is that the entire duration of the vowel is voiced versus a word in which only part of the word may be voiced and part unvoiced over a slightly longer period of time. 67

Table 11. Overall Means and Sid. Dev. of intensity (in dB SPL) of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition.

High Predictability No Noise + Noise SprType Sent Wad Nuc Sent Wad Nuc

Norm 71.7X2.7 67.1X4.1 70.1X4.4 77.3X1.9 74.2X2.3 77.3X2.8 Supra 72.1X4.2 67.2X5.2 70.0X5.3 76.5X3.7 72.9X5.1 76.0X5.3 Hemi 69.1X6.3 66.4X6.1 68.6X6.9 73.2X6.7 70.3X7.0 72.2X7.6 Low Predictability

Norm 71.2X2.6 67.9X3.8 71.6X4.0 77.2X2.0 74.7X2.8 77.7X3.2 Supra 72.5X4.0 68.2X4.9 71.5X5.1 76.5X4.1 73.1X5.0 75.9X5.0 Hemi 69.1X6.6 66.5X6.0 68.4X7.1 72.7X7.2 70.6X7.9 72.6X8.8

The normal speakers displayed little variance from the mean regardless of the noise condition and contextual predictability. Table 50 in Appendix F presents the individual speaker means and standard deviations of intensity of the sentence, key word, and vowel nucleus for the normal speaker group. In the no noise low predictability condition the mean range for sentences is 68.0 dB SPL to 75.4 dB SPL with the standard deviation range being 1.1 dB SPL to 2.1 dB

SPL, for the key word the mean range is 65.6 dB SPL to 74.7 dB SPL with the standard deviation range being 1.6 dB SPL to 3.6 dB SPL, and for the vowel nucleus the mean range is 68.8 dB SPL to 78.6 dB SPL with the standard deviation being 1.7 dB SPL to 3.8 dB SPL. Table 52 in Appendix F displays the means and standard deviations for the individual speakers in the normal group for the sentence, key word, and vowel nucleus in the no noise high predictability condition. The mean range for the sentences is 68.0 dB SPL to 74.8 dB SPL with the standard deviation range being 1.3 dB SPL to 2.0 dB SPL, for the key word the mean range is 64.0 dB

SPL to 73.7 dB SPL with the standard deviation range being 1.9 dB SPL to 3.6 dB SPL, and for the vowel nucleus the mean range is 65.8 dB SPL to 77.0 dB

SPL with the standard deviation range being 1.8 dB to 4.2 dB SPL.

Table 54 in Appendix F displays the means and standard deviations for the individual speakers in the normal group for the sentence, key word, and vowel nucleus in the competing noise low predictability condition. The mean range for the sentences is 75.9 dB SPL to 79.4 dB SPL with the standard deviation range being .86 dB SPL to 2.6 dB SPL, for the key word the mean range is 72.5 dB

SPL to 76.6 dB SPL with the standard deviation range being 1.8 dB SPL to 4.2 dB SPL, for the vowel nucleus the mean range is 74.7 dB SPL to 80.3 dB SPL with the standard deviation range being 1.8 dB SPL to 4.3 dB SPL.

Table 56 in Appendix F displays the means and standard deviations for the individual speakers in the normal group for the sentence, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for the sentences is 75.9 dB SPL to 78.8 dB SPL with the standard deviation range being .74 dB SPL to 1.7 dB SPL, for the key word the mean range is 72.1 dB

SPL to 75.63 dB SPL with the standard deviation range being 1.3 dB SPL to

2.7 dB SPL, and for the vowel nucleus the mean range is 75.0 dB SPL to 78.4 dB SPL with the standard deviation range being 1.6 dB SPL to 3.7 dB SPL.

It is evident that in the presence of competing noise which was 75 dB SPL the normal individual speakers were able to increase the intensity of their voice in 6 order to increase the signal to noise ratio which would likely aid in increasing the intelligibility of the sentence read.

The hemilaryngectomy speakers displayed the most variance from the mean as was evident from the intensity standard deviations. Table 58 in

Appendix F presents the individual speaker means and standard deviations of intensity of the sentence, key word, and vowel nucleus for the hemilaryngectomy speaker group. In the no noise low predictability condition the mean range for sentences is 60.2 dB SPL to 82.6 dB SPL with the standard deviation range being .95 dB SPL to 3.1 dB SPL, for the key word the mean range is 57.7 dB SPL to 77.1 dB SPL with the standard deviation range being

2.0 dB SPL to 3.9 dB SPL, and for the vowel nucleus the mean range is 56.7 dB SPL to 80.7 dB SPL with the standard deviation being 1.9 dB SPL to 3.7 dB SPL.

Table 60 in Appendix F displays the means and standard deviations for the individual speakers in the hemilaryngectomy speaker group for the sentence, key word, and vowel nucleus in the no noise high predictability condition. The mean range for the sentences is 61.8 dB SPL to 81.8 dB SPL with the standard deviation range being .88 dB SPL to 2.1 dB SPL, for the key word the mean range is 58.1 dB SPL to 76.7 dB SPL with the standard deviation range being

1.6 dB SPL to 3.5 dB SPL, and for the vowel nucleus the mean range is 58.3 dB SPL to 79.9 dB SPL with the standard deviation range being 1.7 dB to 3.5 dB SPL.

Table 62 in Appendix F displays the means and standard deviations for the individual speakers in the hemilaryngectomy speaker group for the sentence, key word, and vowel nucleus in the competing noise low predictability condition.

The mean range for the sentences is 61.6 dB SPL to 83.8 dB SPL with the standard deviation range being .68 dB SPL to 2.4 dB SPL, for the key word the mean range is 58.5 dB SPL to 81.0 dB SPL with the standard deviation range being 1.1 dB SPL to 3.9 dB SPL, for the vowel nucleus the mean range is 57.7 dB SPL to 83.8 dB SPL with the standard deviation range being 1.5 dB SPL to

5.6 dB SPL.

Table 64 in Appendix F displays the means and standard deviations for the individual speakers in the hemilaryngectomy speaker group for the sentence, key word, and vowel nucleus in the competing noise high predictability condition.

The mean range for the sentences is 62.0 dB SPL to 83.2 dB SPL with the standard deviation range being .91 dB SPL to 2.4 dB SPL, for the key word the mean range is 58.3 dB SPL to 80.1 dB SPL with the standard deviation range being 1.4 dB SPL to 3.4 dB SPL, and for the vowel nucleus the mean range is

63.8 dB SPL to 83.4 dB SPL with the standard deviation range being 1.6 dB

SPL to 3.1 dB SPL.

By examining the individual hemilaryngectomy speakers' means it was evident that one of the speakers was consistently low in intensity even though he was able to increase the intensity under the competing noise condition but not to the level of 75 dB SPL. It was also evident that another speaker was consistently louder than the other speakers under all conditions. This variability contributed to a larger group standard deviation found in the hemilaryngectomy group.

The supraglottic laryngectomy speakers, like the normal speakers, displayed little variance from the mean regardless of the noise condition and contextual predictability. Table 66 in Appendix F presents the individual speaker means and standard deviations of intensity of the sentence, key word, and vowel nucleus for the supraglottic speaker group. In the no noise low predictability condition the mean range for sentences is 67.3 dB SPL to 80.5 dB SPL with the standard deviation range being .87 dB SPL to 3.0 dB SPL, for the key word the mean range is 62.0 dB SPL to 75.7 dB SPL with the standard deviation range being 1.5 dB SPL to 3.1 dB SPL, and for the vowel nucleus the mean range is

65.7 dB SPL to 78.9 dB SPL with the standard deviation being 1.6 dB SPL to

3.0 dB SPL.

Table 68 in Appendix F displays the means and standard deviations for the individual speakers in the supraglottic speaker group for the sentence, key word, and vowel nucleus in the no noise high predictability condition. The mean range for the sentences is 68.6 dB SPL to 80.7 dB SPL with the standard deviation range being .53 dB SPL to 2.5 dB SPL, for the key word the mean range is

61.6 dB SPL to 75.1 dB SPL with the standard deviation range being 1.9 dB

SPL to 3.7 dB SPL, and for the vowel nucleus the mean range is 64.4 dB SPL to 77.5 dB SPL with the standard deviation range being 1.3 dB to 4.2 dB SPL.

The means and standard deviations for the individual speakers in the supraglottic laryngectomy speaker group for the sentence, key word, and vowel nucleus in the competing noise low predictability condition are displayed in

Table 70 in Appendix F. The mean range for the sentences is 73.2 dB SPL to

85.7 dB SPL with the standard deviation range being 1.0 dB SPL to 2.1 dB

SPL, for the key word the mean range is 67.1 dB SPL to 82.4 dB SPL with the standard deviation range being 1.6 dB SPL to 2.7 dB SPL, for the vowel nucleus the mean range is 69.3 dB SPL to 84.6 dB SPL with the standard deviation range being 1.7 dB SPL to 3.4 dB SPL.

Table 72 in Appendix F displays the means and standard deviations for the individual speakers in the supraglottic laryngectomy speaker group for the sentence, key word, and vowel nucleus in the competing noise high 72 predictability condition. The mean range for the sentences is 73.4 dB SPL to

85.1 dB SPL with the standard deviation range being 1.0 dB SPL to 1.7 dB

SPL, for the key word the mean range is 67.0 dB SPL to 83.0 dB SPL with the standard deviation range being 1.5 dB SPL to 2.8 dB SPL, and for the vowel nucleus the mean range is 67.2 dB SPL to 85.8 dB SPL with the standard deviation range being 1.4 dB SPL to 3.2 dB SPL.

The individual supraglottic laryngectomy speaker means for intensity measures resembled those of the normal speaker means.

The overall means and standard deviations of intensity of the sentence, key word, and the vowel nucleus among speaker types as a function of context predictability are displayed in Table 12. Among speaker types the measures of intensity of the sentence and vowel nucleus are greater than the intensity of the key word regardless of the context predictability. Normal speakers and supraglottic laryngectomy speakers exhibited similar intensity measures for the sentence, key word, and vowel nucleus under the high and low predictability condition. Hemilaryngectomy speakers presented with intensity levels that were approximately 3 dB lower for the sentence, key word, and vowel nucleus when compared to normal and supraglottic laryngectomy speakers regardless of the context predictability. The standard deviations were similar for the normal and 73

Table 12. Overall Means and Std. Dev. of intensity (in dB SPL) of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability.

Context Predictability High Predictability Low Predictability

Spr Type Sent Word Nuc Sent Word Nuc

Norm 74.5X3.6 70.7M.8 73.7X5.1 74.2X3.8 71.2X4.8 74.6V4.7 Supra 74.4X4.5 70.1X5.9 73.1X6.1 74.4X4.5 70.6\5.5 73.6X5.5 Hemi 71.2X6.8 68.4X6.9 70.4X7.4 70.8X7.1 68.5X7.3 70.5X8.2

supraglottic laryngectomy speaker types for the sentences, key word, and vowel nucleus regardless of context predictability. Among the speaker types, the hemilaryngectomy speakers displayed greater variability in comparison to normal speakers and supraglottic speakers for sentences, key word, and vowel nucleus regardless of context predictability.

The overall means and standard deviations of intensity of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition are shown in Table 13. The results showed that intensity increases for the sentence, key word, and vowel nucleus among all speaker types under the presence of competing noise. Looking at the intensity of the sentence, a 5.8 dB average increase was noted for the normals when competing noise was present and a 4.2 dB and 3.9 dB average increase for the supraglottic and hemilaryngectomy speakers, respectively. The measures of intensity are lower for the key word under the no noise condition among speaker types when 74 compared with the intensity of the sentence and vowel nucleus. This pattern is also present under the competing noise condition for all speaker types.

Table 13. Overall Means and Std. Dev. of intensity (in dB SPL) of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition.

Noise Condition

No Noise + Noise

SprType Sent Word Nuc Sent Word Nuc

Norm 71.5\2.7 67.5X3.9 70.9X4.3 77.3X2.0 74.4X2.6 77.5X3.0 Supra 72.3VL1 67.7X5.0 70.9X5.2 76.5X3.9 73.0X5.0 76.0X5.1 Hemi 69. b6.4 66.4X6.0 68.5X7.0 73.0X7.0 70.5X7.4 72.4X8.2

Hemilaryngectomy speakers present with lower intensity levels when compared to normal speakers and supraglottic laryngectomy speakers under no noise and when competing noise was present. The two post surgical speaker groups displayed greater variability in comparison to the normal speakers. The hemilaryngectomy speakers exhibited the greatest variability as displayed by the standard deviation means.

In Table 14, the overall group means and standard deviations of intensity by noise condition as a function of context predictability are displayed. Intensity measures were higher on the sentence, key word, and vowel nucleus under the noise condition regardless of context predictability. The intensity of the key word for both high context predictability and low context predictability was lower under each condition of noise when compared to the intensity measures of the sentence and key word. There was very little variability of intensity noted in either condition of noise regardless of context predictability for the sentence, key word, and vowel nucleus.

Table 14. Overall Means and Std. Dev. of intensity (in dB SPL) by noise condition as a function of context predictability.

Context Predictability

High Predictability Low Predictability

Noise Cond Sent Wad Nuc Sent Wad Nuc

No Noise 70.9X4.8 66.9X5.2 69.6X5.7 70.9X4.9 67.5X5.0 70.5X5.7 + Noise 75.7M.9 72.5X5.4 75.1X6.0 75.5X5.3 72.8X5.8 75.4X6.5

Table 15 displays the overall means and standard deviations of intensity as a function of noise condition. The intensity measures for the sentence, key word, and vowel nucleus were lower under the no noise condition in comparison to the competing noise condition. The intensity of the key word was lower in each condition of noise when compared to the sentence and vowel nucleus There was only a .87 dB SPL difference between measurements of intensity of the sentence and vowel nucleus under the no noise condition and a

.31 dB SPL difference between the measures of intensity of the sentence and vowel nucleus under the competing noise condition. The relationship between the sentences and the vowel nucleus regardless of the noise condition was very similar. Variability of intensity remained fairly constant for the sentence, key word, and vowel nucleus as a function of competing noise. 7 6

Table 15. Overall Means and Std. Dev. of intensity (in dB SPL) for the sentence, key word and vowel nucleus a function of noise.

Intensity Noise Condition Sent Wad Nuc

No Noise 70.9N4.8 67.2X5.1 70.1X5.7 + Noise 75.6X5.1 72.6X5.6 75.3X6.2

The overall means and standard deviations of intensity for the sentence, key word, and vowel nucleus as a function of context predictability are shown in

Table 16. Intensity for the sentence, word and vowel nucleus was greater under the high predictability condition than the low predictability condition. The intensity for the sentence, and vowel nucleus differed only .93 dB SPL under high predictability and .87 dB SPL under low predictability. The intensity of the key word was lower than the intensity of the sentence and vowel nucleus under high predictability and low predictability. There was little variability of intensity for the sentence, key word, and vowel nucleus regardless of context predictability. 77

Table 16 Overall Means and Std. Devs, of intensity (in dB SPL) for the sentence, key word and vowel nucleus as a function of context predictability.

Intensity Context Predictability Sent Word Nuc

High 73.4X5.4 69.8X6.0 72.4X6.4 Low 70.9X4.8 67.2X5.1 70.1X5.7

Table 17 displays the overall means and standard deviations of the intensity for the sentence, key word, and vowel nucleus as a function of speaker type.

The intensity of the sentences was higher across all speaker types followed by the intensity of the vowel nucleus and then the intensity of the key word.

Performance was essentially equal for normal speakers and supraglottic laryngectomy speakers on measurements of intensity for the sentence, key word and vowel nucleus. Intensity measures were lower for the hemilaryngectomy

Table 17 Overall Means and Std. Dev. of intensity (in dB SPL) for the sentence, key word and vowel nucleus as a function of speaker type.

Intensity Spr Type Sent Word Nuc

Norm 74.4X3.7 71.0M.8 74.2X5.0 Supra 74.4X4.5 70.4X5.7 73.4X5.8 Hemi 71.0X7.0 68.5X7.1 70.4X7.8 78 speakers in these three measures as compared to the normal speakers and supraglottic speakers. The hemilaryngectomy speakers showed greater variability in intensity as comparison to the normal speakers and supraglottic speakers for the sentence, key word, and vowel nucleus.

Certain trends were evident from the descriptive statistics regarding intensity: 1) Each speaker group was able to increase intensity when subjected to competing noise regardless of the semantic contextual cues. 2) The post surgical speaker groups are more variable in intensity, with the hemilaryngectomy speakers presenting greatest variability. 3) Although the means are closely related among the sentence, key word, and vowel nucleus, the means of the sentence and nucleus intensity present higher values with greater variability occuring in the vowel nucleus regardless of noise condition and context predictability.

Duration

The means and standard deviations of duration of the sentence, key word, and vowel nucleus are displayed in Tables 18 thru 24. These durational measures are represented in milliseconds. In all tables representing the duration measurements, the duration of the sentence has the longest measurement with the duration of the key word being the next longest and finally the duration of the vowel nucleus being the shortest as would be expected.

Table 18 displays the overall means and standard deviations of duration of the sentence, key word, and vowel nucleus as a function of context predictability and noise conditions. The post surgical groups displayed longer durational Table 18. Overall Means and Std. Dev. (in ms) of duration of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition.

High Predictability

No Noise + Noise

Spr Type Sent Dur Word Dur Nucl Dur Sent Dur Word Dur Nucl Dur

Norm 2010.9X303.6 509.0X096.2 163.5X57.4 2126.5X350.1 521.8X112.6 196.7X80.1 Supra 2365.4X450.9 529.9X123.1 183.CN71.8 2433.5X418.5 601.0X127.4 232.5X95.2 Hemi 2351.4X596.4 577.GN098.0 203.9X63.6 2444.3X624.6 597.8X095.3 239.8X92.5

Low Predictability

Norm 1974.7X341.6 511.2X093.8 164.1X58.1 2103.4X432.5 528.4X117.6 186.6X72.2 Supra 2350.7X491.9 559.4X121.8 178.2X68.8 2433.3X512.3 583.5X140.6 207.2X83.4 Hemi 2332.4X537.2 571.8X087.8 208.3X87.0 2360.3^73.6 584.2X123.2 216.6X75.1

VO times in comparison to the normal speakers for sentences, key words, and vowel nuclei regardless of contextual predictability and noise condition. All speaker groups exhibited slighdy longer durational measures in the presence of competing noise regardless of contextual predictability It is evident that all speaker groups showed variability in duration measures for sentences, key words, and vowel nuclei. For sentence duration measures, the hemilaryngectomy speakers exhibited higher variation from the normals regardless of the noise condition and contextual predictability.

Table 50 in Appendix F displays the individual speaker means and standard deviations of duration of the sentence, key word, and vowel nucleus for the normal speaker group. In the no noise low predictability condition the mean range for sentences is 1646.1 ms. to 2282.0 ms. with the standard deviation range being 158.0 ms. to 352.1 ms., for the key word the mean range is 467.3 ms. to 582.7 with the standard deviation being 68.7 ms. to 119.5 ms., and for the vowel nucleus the mean range is 139.6 ms. to 206.7 ms. with the standard deviation being 30.2 ms. to 100.6 ms.

Table 52 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel nucleus in the no noise high predictability condition. The mean range for

sentences is 1695.6 ms. to 2337.2 ms. with the standard deviation range being

152.2 ms. to 276.8 ms., for the key word the mean range is 452.4 ms. to 620.2

with the standard deviation being 55.41 ms. to 108.3 ms., and for the vowel nucleus the mean range is 137.7 ms. to 205.0 ms. with the standard deviation

being 27.9 ms. to 104.2 ms.

Table 54 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel 8 1 nucleus in the competing noise low predictability condition. The mean range for sentences is 1746.7 ms. to 2580.5 ms. with the standard deviation range being

250.6 ms. to 450.1 ms., for the key word the mean range is 466.9 ms. to 626.9 with the standard deviation being 34.7 ms. to 158.2 ms., and for the vowel nucleus the mean range is 159.3 ms. to 283.6 ms. with the standard deviation being 38.0 ms. to 111.1 ms.

Table 56 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for sentences is 1739.6 ms. to 2557.3 ms. with the standard deviation range being

141.0 ms. to 392.2 ms., for the key word the mean range is 450.4 ms. to 605.3 with the standard deviation being 78.0 ms. to 145.4 ms., and for the vowel nucleus the mean range is 159.0 ms. to 260.4 ms. with the standard deviation being 45.1 ms. to 103.8 ms.

For normal individual speakers, the mean ranges showed slightly longer durational measures for both sentences and vowel nuclei in the competing noise condition as compared to the no noise condition. Word durational measures were the same regardless of the noise condition or context predictability. The normal laryngeal speakers showed little variability among them.

Table 58 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the no noise low predictability condition. The mean range for sentences is 1921.1 ms. to 3281.2 ms. with the standard deviation range being 228.4 ms. to 521.3 ms., for the key word the mean range is 474.9 ms. to

671.6 with the standard deviation being 54.0 ms. to 87.2 ms., and for the vowel 82 nucleus the mean range is 166.3 ms. to 257.8 ms. with the standard deviation being 58.5 ms. to 134.6 ms.

Table 60 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the no noise high predictability condition. The mean range for sentences is 1972.6 ms. to 3256.7 ms. with the standard deviation range being 162.8 ms. to 733.5 ms., for the key word the mean range is 514.6 ms. to

669.4 with the standard deviation being 61.2 ms. to 122.0 ms., and for the vowel nucleus the mean range is 159.1 ms. to 249.3 ms. with the standard deviation being 45.3 ms. to 84.6 ms.

Table 62 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the competing noise low predictability condition. The mean range for sentences is 1933.9 ms. to 3563.4 ms. with the standard deviation range being 213.2 ms. to 757.3 ms., for the key word the mean range is 498.1 ms. to 748.7 with the standard deviation being 31.4 ms. to 181.8 ms., and for the vowel nucleus the mean range is 179.1 ms. to 255.7 ms. with the standard deviation being 33.6 ms. to 114.4 ms.

Table 64 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for sentences is 2094.2 ms. to 3777.9 ms. with the standard deviation range being 157.0 ms. to 609.7 ms., for the key word the mean range is 541.8 ms. to 714.5 with the standard deviation being 29.0 ms. to 116.4 ms., and for the vowel nucleus the mean range is 205.9 ms. to 275.7 ms. with the standard deviation being 59.7 ms. to 132.8 ms. The hemilaryngectomy speakers exhibit a slightly slower rate of speech for sentence duration in the presence of competing noise. Durational mean ranges were the same for the key word regardless of the noise condition and context predictability. This was also exhibited for the vowel nuclei durations.

Table 66 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the no noise low predictability condition. The mean range for sentences is 1947.5 ms. to 2927.7 ms. with the standard deviation range being

291.3 ms. to 468.4 ms., for the key word the mean range is 421.9 ms. to 702.9 with the standard deviation being 37.0 ms. to 141.8 ms., and for the vowel nucleus the mean range is 149.7 ms. to 247.9 ms. with the standard deviation being 66.0 ms. to 83.4 ms.

Table 68 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the no noise high predictability condition. The mean range for sentences is 1880.9 ms. to 2894.9 ms. with the standard deviation range being

220.5 ms. to 509.7 ms., for the key word the mean range is 379.2 ms. to 669.0 with the standard deviation being 67.4 ms. to 169.8 ms., and for the vowel nucleus the mean range is 143.1 ms. to 244.9 ms. with the standard deviation being 26.1 ms. to 100.4 ms.

Table 70 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the competing noise low predictability condition. The mean range for sentences is 2081.8 ms. to 2775.9 ms. with the standard deviation range being 208.3 ms. to 641.5 ms., for the key word the mean range is 454.9 ms. to 770.0 with the standard deviation being 81.2 ms. to 153.7 ms., and for 84 the vowel nucleus the mean range is 173.4 ms. to 286.9 ms. with the standard deviation being 44.0 ms. to 108.2 ms.

Table 72 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for sentences is 1979.8 ms. to 3020.7 ms. with the standard deviation range being 144.9 ms. to 429.0 ms., for the key word the mean range is 473.6 ms. to 755.2 with the standard deviation being 44.5ms. to 149.8 ms., and for the vowel nucleus the mean range is 177.6 ms. to 294.2 ms. with the standard deviation being 50.8 ms. to 141.2 ms.

The supraglottic laryngectomy speakers displayed a slower rate of speech for the entire sentence, key word, and vowel nucleus in the presence of competing noise. Little variability was noted among the individual speakers for duration.

Table 19 displays the overall means and standard deviations of duration of the sentence, key word, and the vowel nucleus among speaker types as a function of context predictability. Among speaker types, the normal speakers exhibit shorter durational measures in comparison to the post surgical groups in

sentences, key words, and vowel nucleus regardless of context predictability.

Durational measures were very similar for the normal speakers as well as for the two post surgical groups for sentence, key word, and vowel nucleus duration

under high predictability and low predictability. The post surgical groups exhibit greater variability for sentence duration as compared to the normal speakers regardless of context predictability. Table 19. Overall Means and Std. Dev. (in ms) of duration of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability.

Context Predictability

High Predictability Low Predictability

Spr Type Sent Dur Word Dur Nucl Dur Sent Dur Word Dur Nucl Dur

Norm 2069.7332.3 515.5X104.8 180.4Y71.6 2038.0X393.2 519/7X106.2 175.2M6.2 Supra 2400.6X434.5 566.A130.0 208.6S88.0 2390.7\502.2 571.1X131.5 192.2X77.4 Hemi 2399.2X611.1 587.7096.9 222.4X81.5 2346.0^05.9 577.9N106.4 212.3X81.3 The overall means and standard deviations of duration of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition are shown in Table 20. The overall individual durational measures for sentences, key words, and vowel nuclei are less under the no noise condition when compared to the competing noise condition. Regardless of the noise condition, the normal speakers displayed shorter durational times for the sentence, key word, and vowel nucleus. The post surgical groups have very similar measures for sentence, key word, and vowel nucleus durations regardless of the noise condition. Duration standard deviations values for the hemilaryngectomy speakers for sentences are around 240 milliseconds longer in duration than normal speakers regardless of the noise condition.

The overall means and standard deviations of duration by noise condition as a function of context predictability are displayed in Table 21. Overall durations for sentences, key words, and vowel nuclei were slightly longer under the competing noise condition regardless of context predictability. Under the no noise condition, sentence duration measures, as well as, word duration and vowel nucleus durations were essentially the same regardless of context predictability. In the no noise condition, little variability was displayed for sentences regardless of the contextual predictability condition.

Table 22. displays the overall means and standard deviations of duration as a function of noise. Duration measures were slightly less under the no noise condition for sentences, key words, and vowel nuclei in comparison to the noise condition. Table 20. Overall Means and Std. Dev. (in ms) of duration of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition.

- Noise + Noise

SprType Sent Dur Word Dur Nucl Dur Sent Dur Word Dur Nucl Dur

Norm 1992.4N323.2 510.1N094.7 163.8\57.6 2115.1N392.1 525.1\114.8 191.7V76.3 Supra 2357.(M71.7 545.5\123.0 180.5V70.1 2433.4M66.0 592.3N134.0 220.0S90.2 Hemi 2341.5^64.7 574.3N092.6 206.A76.5 2402.8N648.8 591.1M09.9 228.3N84.9 Table 21. Overall Means and Std. Dev. (in ms) of duration by noise condition as a function of context predictability.

Context Predictability

High Predictability Low Predictability

Noise Cond Sent Dur Word Dur Nucl Dur Sent Dur Word Dur Nucl Dur

No Noise 2240.3M91.6 538.5X109.7 183.3X66.3 2221.5X494.8 547.8X105.3 183.7X74.4 + Noise 2334.8X499.4 573.5X118.0 223.CN91.1 2299.0X564.7 565.4X129.7 203.5X77.8 Table 22. Overall Means and Std. Dev. (in ms) of duration for the sentence, key word, and vowel nucleus as a function of noise.

Duration

Condition Sent Dur Word Dur Nucl Dur

No Noise 2230.5M92.9 543.3X107.4 183.5X70.6 + Noise 2317.1X532.5 569.5X123.9 213.3X85.3

The overall means and standard deviations of duration for the sentence, key word, and vowel nucleus as a function of context predictability are shown in

Table 23. The length of the key word was essentially the same regardless of context predictability. The length of the sentence and vowel nucleus was slightly longer when contextual cues were given.

Table 23. Overall Means and Std. Dev. (in ms) of duration for the sentence, key word, and vowel nucleus as a function of context predictability.

Duration Pled Sent Dur Word Dur Nucl Dur

High 2288.8M97.4 556.4X115.2 203.7X82.4 Low 2259.3X531.0 556.4X118.0 193.3X76.6

Table 24. displays the overall means and standard deviations of duration of the sentence, key word, and vowel nucleus as a function of speaker type. The 90 sentence, key word, and vowel nucleus durations were slightly less for the normal speakers as compared to the post surgical groups. Durational measures were essentially the same for the post surgical groups when comparing sentence length. Sentence length among the hemilaryngectomy speakers demonstrated greater variability when compared to the normal speakers.

Table 24. Overall Means and Std. Dev. (in ms) of duration for the sentence, key word, and vowel nucleus as a function of speaker type.

Duration

Spr Type Sent Dur Word Dur Nucl Dur

Norm 2053.8X364.0 517.6X105.4 177.8X68.9 Supra 2395.5V169.7 568.9X130.6 200.2S83.0 Hemi 2372.1X608.2 582.7X101.8 217.3X81.4

The trends that were evident for durational measures showed the following: 1) The hemilaryngectomy speakers and supraglottic laryngectomy speakers exhibit longer durational times in comparison to the normal laryngeal speakers for sentences, key words, and vowel nuclei regardless of the noise condition and context predictability. 2) All speakers took slightly longer to read the stimuli when competing noise was present regardless of context predictability. 3) The post surgical groups displayed slightly higher variability in comparison to the normal laryngeal speakers regardless of the noise condition and context predictability. Table 25. Overall Means and Std. Dev of fundamental frequency (Hz) of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition.

High Predictability

No Noise + Noise

SprType Sent FO WordFO Nucl FO Sent FO WordFO Nucl FO

Norm 113.3X18.4 100.6X14.8 97.3X19.1 125.6X20.9 112.4X19.0 109.0X19.7 Supra 107.8X20.0 105.2X53.8 103.6X61.5 114.7X17.4 105.1X29.2 102.2X27.9 Hemi 158.1X44.5 143.8X62.2 133.1X61.9 156.1X38.9 144.5X51.2 143.8X54.3

Low Predictability

Norm 113.1X18.5 104.1X18.1 101.6X18.0 125.3X20.9 116.7X23.1 113.3X23.8 Supra 109.4X20.5 106.2X48.3 106.4X55.3 115.3X18.7 111.5X39.1 113.3X54.3 Hemi 156.0N43.0 142.0x55.5 134.6X58.5 151.9X38.2 136.8X46.3 134.9'60.6 Fundamental Frequency

The overall means and standard deviations of fundamental frequency of the sentence, key word, and vowel nucleus as a function of context predictability and noise condition are exhibited in Table 25. The results showed that regardless of noise condition and context predictability, hemilaryngectomy speakers had higher fundamental frequencies for sentences, key words, and vowel nuclei when compared to normal and supraglottic laryngectomy speaker types. Under the presence of competing noise and regardless of context predictability, the normal and supraglottic speakers displayed an increase in the fundamental frequency of the sentence, whereas, the hemilaryngectomy speakers exhibited a decrease. Hemilaryngectomy speakers displayed greater variability in comparison to normal and supraglottic laryngectomy speakers regardless of noise condition and context predictability.

Table 51 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel nucleus in the no noise low predictability condition. The mean range for sentences is 88.8 Hz. to 141.4 Hz. with the standard deviation range being 2.0

Hz. to 9.4 Hz., for the key word the mean range is 81.9 Hz. to 130.1 Hz with the standard deviation being 3.4 Hz. to 15.9 Hz, and for the vowel nucleus the mean range is 79.7 Hz to 125.1 Hz with the standard deviation being 5.4 Hz to

16.2 Hz.

Table 53 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel nucleus in the no noise high predictability condition. The mean range for sentences is 88.4 Hz. to 136.4 Hz. with the standard deviation range being 1.7

Hz. to 9.8 Hz., for the key word the mean range is 82.5 Hz. to 116.8 Hz with 93 the standard deviation being 2.2 Hz. to 16.9 Hz, and for the vowel nucleus the mean range is 80.8 Hz to 119.3 Hz with the standard deviation being 3.8 Hz to

34.8 Hz.

Table 55 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel nucleus in the competing noise low predictability condition. The mean range for sentences is 100.9 Hz. to 155.6 Hz. with the standard deviation range being 2.2

Hz. to 8.9 Hz., for the key word the mean range is 89.1 Hz. to 152.6 Hz with the standard deviation being 3.5 Hz. to 18.9 Hz, and for the vowel nucleus the mean range is 87.0 Hz to 152.7 Hz with the standard deviation being 3.7 Hz to

28.6 Hz.

Table 57 in Appendix F exhibits the means and standard deviations for the individual speakers in the normal group for the sentences, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for sentences is 100.4 Hz. to 154.4 Hz. with the standard deviation range being 2.7

Hz. to 8.6 Hz., for the key word the mean range is 92.8 Hz. to 136.1 Hz with the standard deviation being 3.9 Hz. to 18.2 Hz, and for the vowel nucleus the mean range is 89.1 Hz to 134.6 Hz with the standard deviation being 6.4 Hz to

23.8 Hz.

It is evident that fundamental frequency among normal speakers increased in the presence of competing noise regardless of contextual cues. The normal speakers exhibited the same variance in fundamental frequency in the sentences regardless of the noise condition and context predictability.

Table 59 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the no noise low predictability condition. The mean range for sentences is 86.7 Hz. to 206.7 Hz. with the standard deviation range being

4.3 Hz. to 34.4 Hz., for the key word the mean range is 75.5 Hz. to 211.3 Hz with the standard deviation being 4.6 Hz. to 77.3 Hz, and for the vowel nucleus the mean range is 69.3 Hz to 211.9 Hz with the standard deviation being 4.9 Hz to 73.0 Hz.

Table 61 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the no noise high predictability condition. The mean range for sentences is 86.9 Hz. to 205.5 Hz. with the standard deviation range being

3.6 Hz. to 30.3 Hz., for the key word the mean range is 74.1 Hz. to 199.9 Hz with the standard deviation being 4.2 Hz. to 123.8 Hz, and for the vowel nucleus the mean range is 72.3 Hz to 198.2 Hz with the standard deviation being

4.9 Hz to 97.5 Hz.

Table 63 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the competing noise low predictability condition. The mean range for sentences is 96.1 Hz. to 187.2 Hz. with the standard deviation range being 3.2 Hz. to 37.2 Hz., for the key word the mean range is 90.9 Hz. to

180.7 Hz with the standard deviation being 7.5 Hz. to 65.8 Hz, and for the vowel nucleus the mean range is 85.6 Hz to 184.8 Hz with the standard deviation being 7.5 Hz to 115.7 Hz.

Table 65 in Appendix F exhibits the means and standard deviations for the individual speakers in the hemilaryngectomy group for the sentences, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for sentences is 94.7 Hz. to 196.5 Hz. with the standard deviation range being 3.2 Hz. to 32.5 Hz., for the key word the mean range is 94.9 Hz. to 187.5 Hz with the standard deviation being 5.7 Hz. to 93.5 Hz, and for the vowel nucleus the mean range is 94.0 Hz to 185.7 Hz with the standard deviation being 9.1 Hz to 100.4 Hz.

The lowest fundamental frequency for the hemilaryngectomy speakers increased under the presence of competing noise for sentences, key words, and vowel nuclei; however, the hemilaryngectomy speakers' highest fundamental frequency decreased under the presence of competing noise regardless of the contextual predictability. Among the hemilaryngectomy speakers variability for sentences, key words and vowel nuclei are evident.

Table 67 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the no noise low predictability condition. The mean range for sentences is 86.9 Hz. to 148.8 Hz. with the standard deviation range being 2.4

Hz. to 22.4 Hz., for the key word the mean range is 80.5 Hz. to 144.9 Hz with the standard deviation being 5.2 Hz. to 112.0 Hz, and for the vowel nucleus the mean range is 76.9 Hz to 151.7 Hz with the standard deviation being 3.8 Hz to

118.8 Hz.

Table 69 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the no noise high predictability condition. The mean range for sentences is 87.1 Hz. to 148.5 Hz. with the standard deviation range being 2.1

Hz. to 22.7 Hz., for the key word the mean range is 78.4 Hz. to 146.8 Hz with the standard deviation being 3.6 Hz. to 144.7 Hz, and for the vowel nucleus the mean range is 75.0 Hz to 143.5 Hz with the standard deviation being 4.3 Hz to

136.9 Hz. 96 Table 71 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the competing noise low predictability condition. The mean range for sentences is 104.2 Hz. to 160.2 Hz. with the standard deviation range being 2.1 Hz. to 23.8 Hz., for the key word the mean range is 87.5 Hz. to

156.6 Hz with the standard deviation being 4.1 Hz. to 87.2 Hz, and for the vowel nucleus the mean range is 84.7 Hz to 164.4 Hz with the standard deviation being 5.9 Hz to 121.3 Hz.

Table 73 in Appendix F exhibits the means and standard deviations for the individual speakers in the supraglottic group for the sentences, key word, and vowel nucleus in the competing noise high predictability condition. The mean range for sentences is 102.7 Hz. to 155.3 Hz. with the standard deviation range being 2.9 Hz. to 13.7 Hz., for the key word the mean range is 86.3 Hz. to

141.4 Hz with the standard deviation being 4.0 Hz. to 37.0 Hz, and for the vowel nucleus the mean range is 84.7 Hz to 131.2 Hz with the standard deviation being 4.3 Hz to 43.7 Hz.

Supraglottic laryngectomy speakers demonstrated higher fundamental frequency measures under the presence of competing noise for sentences, key words, and vowel nucleus with the exception of the highest fundamental frequency in key words and vowel nuclei under the high predictability condition.

Here the highest fundamental frequency was in the no noise condition.

Inspecting the individual speaker's means, one supraglottic speaker showed the greatest variability.

Table 26 displays the overall means and standard deviations of fundamental frequency of the sentence, key word, and the vowel nucleus among speaker types as a function of context predictability. Among speaker types, the Table 26. Overall Means and Std. Dev. of fundamental frequency (Hz) of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability.

Context Predictability

High Predictability Low Predictability

SprType Sent FO WordFO Nucl FO Sent FO WordFO Nucl F0

Norm 119.5V20.6 106.6X18.0 103.3X20.2 119.1X20.6 110.3X21.6 107.4X21.8 Supra 111.4\19.0 105.2M2.8 102.9M7.1 112.3X19.8 108.8X44.1 109.8X54.8 Hemi 157.1X41.6 144.1X56.6 138.6X58.2 154.0X40.7 139.5X51.1 134.8X59.4 hemilaryngectomy speakers demonstrated higher fundamental frequency in

comparison to normal and supraglottic laryngectomy speakers in sentences, key

words, and vowel nuclei regardless of context predictability. Hemilaryngectomy

speakers display greater variability regardless of context predictability.

The overall means and standard deviations of fundamental frequency of the

sentence, key word, and vowel nucleus among speaker types as a function of

noise condition are shown in Table 27. The results showed that among speaker

types, hemilaryngectomy speakers consistently displayed higher fundamental

frequency for the sentence, key word, and vowel nucleus in comparison to

normal and supraglottic laryngectomy speakers regardless of noise condition.

Within the normal speaker group, higher fundamental frequencies were evident

in the competing noise condition for sentence, key word, and vowel nucleus.

This was also exhibited by the supraglottic laryngectomy speakers. The

hemilaryngectomy speakers showed higher fundamental frequency for the

sentence and key word under the no noise conditions. The two post surgical

groups showed the greatest variability in comparison to the normal speakers in

the presence of competing noise.

In Table 28 the overall means and standard deviations of fundamental

frequency by noise condition as a function of context predictability are

displayed. Fundamental frequency was higher under the competing noise

condition for sentence, key word, and vowel nucleus regardless of the context

predictability. There was tittle difference between the sentence, key word, and

vowel nucleus fundamental frequency in the no noise condition under high

predictability versus the no noise condition low predictability. This was also

true under the competing noise condition high predictability and competing noise

condition low predictability. Table 27. Overall Means and Std. Dev. of fundamental frequency (Hz) of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition.

Noise Condition

No Noise + Noise

Spr Type Sent FO WordFO Nucl FO Sent FO WordFO Nucl FO

Norm 113.2\18.4 102.4X16.6 099.5X18.6 125.5N20.8 114.5X21.2 111.1X21.9 Supra 108.7X20.2 105.8X50.8 105.1\58.2 115.0M8.0 108.3X34.5 107.7X43.3 Hemi 157.CM3.6 142.8S58.6 133.9S60.0 154.0X38.5 140.7X48.8 139.4X57.5 Table 28. Overall Means and Std. Dev. of fundamental frequency (Hz) by noise condition as a function of context predictability.

Context Predictability

High Predictability Low Predictability

Noise Cond Sent FO WordFO Nucl FO Sent FO WordFO Nucl FO

No Noise 126.4X37.5 116.4X51.6 111.3X53.5 126.2X36.3 117.5X47.1 114.3M9.8 + Noise 132.1X32.5 120.7X39.5 118.3X41.2 130.8X31.3 121.7X38.9 120.5M9.8 100 Table 29 displays the overall means and standard deviations of the fundamental frequency for the sentence, key word, and vowel nucleus as a function of noise condition. The fundamental frequency of the sentence, key word, and vowel nucleus was higher under the competing noise condition in comparison to the no noise condition. The range was from 5.19 Hz higher for sentences, and 4.19 Hz and 6.65 Hz higher for the key word and vowel nucleus respectively. Regardless of the noise condition, sentences had the highest fundamental frequency followed by the key word and vowel nucleus.

Table 29 Overall Means and Std. Dev. of fundamental frequency (Hz) for the sentence, key word, and vowel nucleus as a function of noise condition.

Fundamental Frequency

Condition Sent FO Word FO Nucl FO

No Noise 126.3X36.8 117.0X49.3 112.9X51.6 + Noise 131.5X31.9 121.2X39.2 119.4M5.6

The overall means and standard deviations of fundamental frequency of the sentence, key word, and vowel nucleus as a function of context predictability are displayed in Table 30. The fundamental frequency of the sentence, key word, and vowel nucleus of the high predictability condition was similar in comparison to the sentence, key word, and vowel nucleus of the low predictability. A .86

Hz difference is shown between the high predictability and low predictability condition for the sentence followed by a .94 Hz difference in the key word and a

2.4 Hz difference in the vowel nucleus. 102

Table 30. Overall Means and Std. Dev. of fundamental frequency (Hz) for the sentence, key word and vowel nucleus as a function of context predictability.

Fundamental Frequency

Pied Sent FO WordFO Nucl FO

High 129.3N35.1 118.6M5.8 114.9N47.7 Low 128.5V34.0 119.5\43.3 117.3M9.9

Table 31 displays the overall means and standard deviations of fundamental frequency of the sentence, key word, and vowel nucleus as a function of speaker type. The fundamental frequency of the hemilaryngectomy speakers was higher for the sentence, key word, and vowel nucleus when compared to normal and supraglottic laryngectomy speakers. The fundamental frequency for the normal speakers and supraglottic laryngectomy speakers were very similar for the sentence, key word, and vowel nucleus. The sentence fundamental frequency for the normal speakers measured 7.5 Hz higher than the supraglottic laryngectomy speakers and the hemilaryngectomy speakers were

36.2 Hz greater than normal speakers. Sentences were higher in fundamental frequency than the key word and vowel nucleus for all three speaker types. Per speaker types, the key word and vowel nucleus fundamental frequency were similar. The supraglottic laryngectomy speakers and the hemilaryngectomy speakers displayed greater variability in comparison to normal speakers. 103

Table 31. Overall Means and Std. Dev. of fundamental frequency (Hz) for the sentence, key word, and vowel nucleus as a function of speaker type.

Fundamental Frequency Spr Type Sent FO Word FO Nucl FO

Norm 119.3X20.6 108.4\20.0 105.3X21.1 Supra 111.8M9.4 107.0X43.4 106.4X51.2 Hemi 155.5V41.1 141.8X53.9 136.768.8

Certain trends were evident regarding fundamental frequency: 1) Mean fundamental frequency was the highest in the hemilaryngectomy speakers for sentences, key words, and vowel nuclei in comparison to normal laryngeal speakers and supraglottic laryngectomy speakers regardless of noise condition and context predictability. 2) Greater variability of fundamental frequency was shown in the hemilaryngectomy speakers. 3) The mean fundamental frequency was the highest in sentences for all speaker groups.

Voicing

The overall means and standard deviations of the percentage of voicing in sentences, key words, and vowel nuclei as a function of context predictability and noise condition are displayed in Table 32.The normal laryngeal speakers displayed a higher percentage of voicing in the no noise/high predictability condition and low predictability condition for sentences, key words, and vowel Table 32. Overall Means and Std. Dev of percentage of voicing of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability and noise condition.

High Predictability

No Noise + Noise

SprType % Voice Sent % Voice Word % Voice Nucl % Voice Sent % Voice Word % Voice Nucl Z l l i 59.9X11.9 44.4X20.0 81.5X22.4 60.(N)9.0 46.2X14.0 83.7X17.7 m 57.413.1 40.0\20.0 73.6X25.2 61.1X10.6 48.1X15.9 87.4X16.4 EC 54.0x20.3 41.9X22.7 73.6S32.4 58.8X14.8 46.6X19.3 76.2X26.0

Low Predictability

Norm 56.3X08.4 42.1X16.4 84.6517.8 59.4N09.1 49.6X17.2 88.6X15.7 Supra 52.4\09.1 37.6X13.7 78.1N20.2 59.4X10.6 49.2M6.2 84.9X19.1 Hemi 51.9M6.8 39.6x20.0 71.8531.9 55.5X15.6 46.2X19.9 77.1X31.1 4 0 1 nuclei. The supraglottic laryngectomy speakers exhibited a higher percentage of voicing in the competing noise/high predictability condition for sentences, key words, and vowel nuclei. Under the competing noise/low predictability condition, the supraglottic laryngectomy speakers displayed higher percentage of voicing for sentences but the normal speakers showed higher percentage of voicing for key words and vowel nuclei. The hemilaryngectomy speakers displayed the greatest variability regardless of noise condition and context predictability.

Table 51 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for normal speakers. In the no noise low-predictability condition the mean range for sentences is 49.4 % to 64.8 % with the standard deviation range being 4.9% to 10.1%, for the key word the mean range is

29.9% to 52.0% with the standard deviation range being 9.5% to 21.4%, and for the vowel nucleus the mean range is 68.9% to 98.5% with the standard deviation range being 4.9% to 22.3%.

Table 53 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for normal speakers. In the no noise high-predictability condition the mean range for sentences is 48.6 % to 76.1 % with the standard deviation range being 7.2% to 12.7%, for the key word the mean range is

27.6% to 62.9% with the standard deviation range being 8.9% to 22.2%, and for the vowel nucleus the mean range is 56.4% to 99.5% with the standard deviation range being 1.5% to 31.4%.

Table 55 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, 106 and vowel nuclei for normal speakers. In the competing noise low-predictability condition the mean range for sentences is 50.4 % to 68.8 % with the standard deviation range being 4.7% to 9.7%, for the key word the mean range is 39.9% to 66.0% with the standard deviation range being 11.0% to 22.5%, and for the vowel nucleus the mean range is 79.6% to 99.4% with the standard deviation range being 1.8% to 21.0%.

Table 57 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for normal speakers. In the competing noise high- predictability condition the mean range for sentences is 50.5 % to 70.9 % with the standard deviation range being 3.5% to 9.4%, for the key word the mean range is 34.1% to 61.2% with the standard deviation range being 6.5% to

14.7%, and for the vowel nucleus the mean range is 71.4% to 96.3% with the standard deviation range being 8.7% to 25.9%.

For normal speakers, the percentage of voicing increases under the presence of competing noise. The percentage of voicing was greater for the vowel nucleus which would be the expected result since all vowels are voiced.

Within sentences, key words, and vowel nuclei, voicing did not differ as a result of noise condition or context predictability.

Table 59 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the no noise low- predictability condition the mean range for sentences is 26.8 % to 71.3 % with the standard deviation range being 4.4% to 17.0%, for the key word the mean range is 16.5% to 53.7% with the standard deviation range being 11.5% to 107 20.1%, and for the vowel nucleus the mean range is 26.0% to 93.8% with the standard deviation range being 6.9% to 28.8%.

Table 61 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the no noise high- predictability condition the mean range for sentences is 23.5 % to 75.6 % with the standard deviation range being 7.6% to 15.0%, for the key word the mean range is 14.3% to 58.5% with the standard deviation range being 12.2% to

24.4%, and for the vowel nucleus the mean range is 26.4% to 99.0% with the standard deviation range being 3.0% to 39.0%.

Table 63 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the noise low-predictability condition the mean range for sentences is 34.3 % to 70.0 % with the standard deviation range being 6.2% to 13.2%, for the key word the mean range is

22.4% to 63.1% with the standard deviation range being 10.1% to 18.7%, and for the vowel nucleus the mean range is 29.9% to 97.1% with the standard deviation range being 5.6% to 39.5%.

Table 65 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the competing noise high- predictability condition the mean range for sentences is 39.8 % to 73.2 % with the standard deviation range being 6.3% to 13.4%, for the key word the mean range is 24.7% to 62.7% with the standard deviation range being 9.1% to

20.3%, and for the vowel nucleus the mean range is 34.0% to 94.3% with the standard deviation range being 8.1% to 28.7%. 1 The percentage of voicing is slightly higher for the hemilaryngectomy speakers under the competing noise condition. Speaker variability appeared to be higher for the vowel nucleus among the hemilaryngectomy speakers.

Table 67 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for supraglottic laryngectomy speakers. In the no noise low- predictability condition the mean range for sentences is 44.0 % to 58.9 % with the standard deviation range being 3.2% to 10.4%, for the key word the mean range is 26.3% to 45.3% with the standard deviation range being 7.3% to

18.0%, and for the vowel nucleus the mean range is 54.4% to 93.3% with the standard deviation range being 7.4% to 30.8%.

Table 69 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the no noise high- predictability condition the mean range for sentences is 48.4 % to 65.3 % with the standard deviation range being 8.5% to 15.3%, for the key word the mean range is 20.4% to 59.3% with the standard deviation range being 12.6% to

22.5%, and for the vowel nucleus the mean range is 43.5% to 92.0% with the standard deviation range being 15.4% to 29.6%.

Table 71 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the competing noise low- predictability condition the mean range for sentences is 48.3 % to 69.6 % with the standard deviation range being 6.9% to 11.0%, for the key word the mean range is 29.8% to 65.9% with the standard deviation range being 8.6% to 109 16.7%, and for the vowel nucleus the mean range is 54.4% to 98.1% with the standard deviation range being 3.2% to 30.7%.

Table 73 in Appendix F displays the individual speaker means and standard deviations of the percentage of voicing of the sentences, key words, and vowel nuclei for hemilaryngectomy speakers. In the competing noise high- predictability condition the mean range for sentences is 51.2 % to 70.0 % with the standard deviation range being 4.6% to 10.9%, for the key word the mean range is 36.7% to 52.0% with the standard deviation range being 9.9% to

20.6%, and for the vowel nucleus the mean range is 66.3% to 96.2% with the standard deviation range being 5.1% to 24.7%.

The percentage of voicing is slightly higher for the supraglottic laryngectomy speakers under the competing noise condition. Within sentences, key words, and vowel nuclei, speaker variability did not differ as a result of noise condition and context predictability.

Table 33 displays the overall means and standard deviations of the percentage of voicing of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability. Normal speakers exhibited the highest percentage of voicing in sentences, key words, and vowel nuclei in comparison to the post surgical groups regardless of the context predictability.

The hemilaryngectomy speakers displayed the greatest variability in the percentage of voicing as compared to normal laryngeal speakers and supraglottic laryngectomy speakers.

Table 34 displays the overall means and standard deviations of the percentage of voicing of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition. The results showed the percentage of voicing is higher for the sentence, key word, and vowel nucleus Table 33. Overall Means and Std. Dev. of percentage of voicing of the sentence, key word, and vowel nucleus among speaker types as a function of context predictability.

Context Predictability

High Predictability Low Predictability

SprType % Voice Sent % Voice Word % Voice Nucl % Voice Sent % Voice Word % Voice Nucl

Norm 59.9X10.5 45.3X17.2 82.6X20.1 57.8X08.9 45.8X17.1 86.6X16.9 Supra 59.3X12.0 44.2X18.4 80.8X22.2 55.8X10.4 43.2X16.0 81.4X19.9 Hemi 56.4X17.8 44.3X21.1 75.0X29.2 53.6X16.3 42.8X20.2 74.4X31.5 110 Table 34. Overall Means and Std. Dev. of percentage of voicing of the sentence, key word, and vowel nucleus among speaker types as a function of noise condition.

Noise Condition

No Noise + Noise

Spr Type % Voice Sent % Voice Word % Voice Nucl % Voice Sent % Voice Word % Voice Nucl

Norm 58.CM0.4 43.2X18.2 83.1X20.2 59.7X09.0 47.9X15.7 86.1X16.9 Supra 54.8M1.4 38.7U7.0 76.0N22.8 60.2S10.6 48.6S16.0 86.2M7.7 Hemi 52.9\18.5 40.7N21.3 72.7V32.1 57.2M5.2 46.4X19.6 76.7X28.5 Table 35. Overall Means and Std. Dev. of percentage of voicing by noise condition as a function of context predictability.

Context Predictability

High Predictability Low Predictability

Noise Cond % Voice Sent % Voice Word % Voice Nucl % Voice Sent % Voice Word % Voice Nucl

No Noise 57.1N15.7 42.1X20.9 76.3N27.1 53.5X12.2 39.7X16.9 78.1X24.6 + Noise 59.9X11.7 47 .CM 6.5 82.5^0.9 58.1X12.2 48.3X17.8 83.5X23.3 for all speaker types under the noise condition. Under the no noise condition, the normal speakers exhibited a higher percentage of voicing for the sentences, key words, and vowel nuclei when compared to the post surgical groups. The supraglottic speakers had the highest percentage of voicing under the competing noise condition for the sentences, key words, and vowel nuclei. The hemilaryngectomy showed the greatest variability in comparison to the normal speakers and supraglottic laryngectomy speakers.

The overall means and standard deviations of the percentage of voicing by noise condition as a function of context predictability is shown in Table 35. The percentage of voicing was higher in the competing noise condition for sentences, key words, and vowel nuclei regardless of context predictability.

Table 36 displays the overall means and standard deviations in the percentage of voicing in the sentences, key words, and vowel nucleus as a function of noise. The percentage of voicing was greater for the sentences, key words, and vowel nucleus under the competing noise condition This ranged from 3.80 percent higher under the competing noise condition for sentences and

6.75 and 5.73 percent higher for the key word and vowel nucleus respectively.

The vowel nucleus had greater percentage of voicing followed by the sentence and the key word, regardless of the noise condition. 114

Table 36. Overall Means and Std. Dev of percentage of voicing for the sentence, key word, and vowel nucleus as a function of noise.

% of Voicing

Condition % Voice Sent % Voice Word % Voice Nucl

No Noise 55.2X14.1 40.9X19.0 77.3X25.8 + Noise 59.0X12.0 47.6X17.2 83.0X22.1

The overall means and standard deviations for the percentage of voicing for the sentences, key words, and vowel nuclei as a function of context predictability are displayed in Table 37. The percentage of voicing was only

2.84 percent higher for sentences and .69 percent higher for the key word in high predictability versus the low predictability. The percent of voicing was

1.30 percent higher for the vowel nucleus in the low predictability The vowel nucleus had the greatest percentage of voicing regardless of the context predictability.

Table 37. Overall Means and Std. Dev. of percentage of voicing for the sentence, key word, and vowel nucleus as a function of context predictability.

% of Voicing Pled % Voice Sent % Voice Word % Voice Nucl

High 58.6X13.8 44.6U8.9 79.5X24.3 Low 55.7X12.4 43.9X17.9 80.8X24.1 Table 38 displays the overall means and standard deviations for the percentage of voicing in the sentence, key word, and vowel nucleus as a function of speaker type. The normal speakers displayed higher percentage of voicing in sentences, key words, and vowel nuclei in comparison to the two post surgical groups. Hemilaryngectomy speakers exhibit lower percentage of voicing in comparison to the normal and supraglottic laryngectomy speaker groups for the sentences, key words, and vowel nuclei. The percentage of voicing in the sentences varied little among speaker groups as well as the key words. The percentage of voicing differed by 9.92 percent in the vowel nuclei between normal speakers and hemilaryngectomy speakers

Table 38. Overall Means and Std. Dev. of percentage of voicing for the sentence, key word, and vowel nucleus as a function of speaker type.

% of Voicing

Spr Type % Voice Sent % Voice Word % Voice Nucl

Norm 58.9X09.7 45.5X17.2 84.6X18.7 Supra 57.5X11.3 43.7X17.2 81.1X21.0 Hemi 55.0X17.1 43.6X20.6 74.7X30.4

The trends that were evident regarding voicing are as follows: 1) All speaker types displayed an increase in the percentage of voicing under the presence of competing noise. 2) Normal laryngeal speakers exhibited a higher percentage of voicing overall in comparison to the two post surgical groups. 3)

The normal laryngeal speakers displayed the highest percentage of voicing in the no noise condition regardless of context predictability; however, the supraglottic 116 laryngectomy speakers exhibited a higher percentage of voicing under the competing noise/high predictability condition and for sentences in the competing noise/low predictability condition. 4) Hemilaryngectomy speakers displayed the greatest variability among the speaker types.

This completes the descriptive statistics of the acoustical measures. The next part of this chapter explains the statistics used to examine the descriptive acoustical variables and the relationship of these variables to the perceptual part of the investigation.

Principal Components Analyses of Acoustical Parameters

The 12 acoustical variables measured in this investigation were intensity of the word, sentence, and vowel nucleus; duration of the sentence, word and vowel nucleus; mean fundamental frequency of the sentence, word, and vowel nucleus; and percentage of voicing of the sentence, word, and vowel nucleus.

To reduce the number of continuous variables to the least redundant set of measures which would account for the most variance in the data, principal component analyses (Data Desk, 1989) were performed separately on the correlation matrices of intensity, duration, mean fundamental frequency, and percentage of voicing parameters. The first principal component of the acoustical variables for each analysis was then selected to be incorporated in the model that will be explained later in this chapter.

Intensity

The results of the principal components analysis of intensity are presented in Table 39. This matrix displays the variables of intensity (dB) of the sentence, word, and vowel nucleus and three factors that have been extracted. By examining the unrotated factor matrix, the variables dB sentence, dB word, and dB nucleus have relatively high loadings on Factor I (-0.949, -0.977, and -

0.971, respectively) while having relatively low loadings on Factor II (-0.314,

0.125, and 0.181, respectively) and Factor III (-0.020, 0.173, and -0.154, respectively). The first factor then accounted for 93.3% of the total variance which also has the highest eigenvalue (simply the amount of variance in the data explained by that factor). Factor II accounted for 4.9% of the variance and

Factor III for 1.8% of the variance. Based on this analyses the first principal component will be used in the model for further statistical analyses.

Table 39. Unrotated factor matrix and eigenvalues of intensity measures

Factors Eigen Vectors Variables I n m VI V2 V3 dBsent 0.949 0.314 0.020 0.567 0.819 0.086 dBwcxd 0.977 0.125 0.173 0.584 0.326 0.743 dBnuc 0,971 0.181 0.154 0.581 0.472 0.663 Variance 2.799 0.147 0.054 Prop, total 93.3 4.9 1.8 variance

Mean Fundamental Frequency

The results of the principal components analysis of mean fundamental frequency are presented in Table 40. This matrix displays the variables of mean fundamental frequency of the sentence, word, and vowel nucleus. Examination of the unrotated factor matrix, showed the variables mean fundamental frequency of the sentence (sfmean), mean fundamental frequency of the word (wfmean), and mean fundamental frequency of the vowel nucleus (nfmean) have relatively high loadings on Factor I (-0.825, -0.949, and -0.915, respectively) while having relatively lower loadings on Factor II (-0.562, 0.167, and 0.333, respectively) and relatively low loadings on Factor in (0.055, -0.265, and

0.226, respectively). The first factor then accounted for 80.7% of the total variance. Factor n accounted for 15.2% of the variance and Factor III for 4.2% of the variance. From these findings the first principal component will be included in the model for further statistical analyses.

Table 40. Unrotated factor matrix and eigenvalues of mean fundamental frequency measures

Factors Eigen Vectors

Variables I n m vi V2 V3 sfmean 0.825 0.562 0.055 0.530 0.833 0.156 wfrnean 0.949 0.167 0.265 0.610 0.248 0.752 nfrnean 0.915 0.333 0,226 0.588 0.494 0.640 Variance 2.420 0.455 0.125 Prop, total 80.7 15.2 4.2 variance

Percentage of Voicing

The results of the principal components analysis of percentage of voicing are presented in Table 41.This matrix displays the variables of percentage of voicing of the sentence, word, and vowel nucleus. Examination of the unrotated factor matrix, showed the variables percentage of voicing of the sentence

(svoic), percentage of voicing of the word (wvoic), and percentage of voicing of the vowel nucleus (nvoic) have relatively high loadings on Factor I (-0.849, -

0.882, and -0.825, respectively) while having relatively lower loadings on 119 Factor II (0.419,0.102, and -0.541, respectively) and on Factor HI (-0.320,

0.459, and -0.161, respectively). The first factor then accounted for 72.7% of the total variance. Factor n accounted for 16.0% of the variance and Factor HI for 11.3% of the variance. It was concluded that the first principal component be included in the model for further statistical analyses.

Table 41. Unrotated factor matrix and eigenvalues of percentage of voicing measures

Factors Eigen Vectors Variables I n m VI V2 V3 svoic 0.849 0.419 0.320 0.575 0.606 0.550 wvoic 0.882 0.102 0.459 0.597 0.148 0.788 nvoic 0.825 0.541 0.161 0.559 0.782 0.277 Variance 2.182 0.479 0.339 Prop, total 72.7 16.0 11.3 variance

Duration

The results of the principal components analysis of duration are presented in Table 42. This matrix displays the variables of the duration of the sentence, word, and vowel nucleus. Examination of the unrotated factor matrix, showed the variables of sentence duration (sentdur), word duration (worddur), and vowel nucleus duration (nucdur) have relatively high loadings on Factor I . The first factor accounted for 53.2% of the total variance. Factor II accounted for

28.4% of the variance and Factor III for 18.3% of the variance. Since the first principal component explained only 53% of the variance with the second component equalling 28% of the variance it was necessary to create a new variable to include the second component.

Table 42. Unrotated factor matrix and eigenvalues of duration measures

Factors Eigen Vectors Variables I n m VI V2 V3 sentdur 0.746 0.489 0.452 0.591 0.529 0.609 worddur 0.824 0.122 0.554 0.652 0.132 0.747 nucdur 0,001 0,774 0,198 0.476 0.838 0.267 Variance 1.597 0.853 0.550 Prop, total 53.2 28.4 18.3 variance

It is also shown that nucleus duration measures load on factor EL Since the first principal component accounted for only 53% of the total variance, a new variable was created by taking the nucleus duration and dividing it by the sentence duration. This variable, abbreviated ns, was included with the first principal component and these two variables were used in the model for further statistical analyses.

General Linear Model

Knowing the outcome of the perceptual analysis using logistic regression

(see above) and the results of the principal component analysis, this investigator used the general linear model (SAS, 1989) to determine how the acoustical variables influenced intelligibility of speech among the vertical partial laryngectomy speakers, the horizontal partial laryngectomy speakers, and the normal laryngeal speakers. The following will discuss the models which incorporated the dependent and independent variables

Since all the speakers heard 75 dB SPL of white noise it was theorized that by increasing the intensity to above 75 dB SPL to increase the signal-to-noise ratio then intelligibility should also improve. A new indicator variable was created which was called cutdbA. This variable took the first principal component into account. If the principal component weighted average for intensity was greater than 75 dB SPL then a 1 was assigned to the variable cutdbA otherwise a 0 was assigned.

The principal components (see above) created four indices including the four factors of fundamental frequency (fundamental frequencypCa), percentage of voicing (voicingpCa), intensity (intensitypCa), and duration (durationpCa).

Durationpca as noted above included the first principal component and the variable ns. The initial general linear model included the log odds as the dependent variable and the independent variables of speaker type, noise condition, context predictability, and speaker nested within speaker type, the composite acoustical variables from the principal component indices which included fundamental frequencypca, intensitypCa, voicingpCa, durationpc^, and ns, and all possible two-way interactions and the three-way interaction of speaker type by noise condition by context predictability. The interactions of cutdbA with noise, context predictability, and speaker type were also included in the model.

With the alpha level set a priori at 0.05, the initial model using general linear regression analysis retained the following variables and interactions as significant: speaker type, noise condition, context predictability, speaker nested within speaker type, intensitypCa, and the two-way interactions of intensitypca with noise condition, fundamental frequencypCa with noise condition, intensitypCa with speaker type, noise condition with context predictability, and speaker type with context predictability.

Speech intelligibility is governed by many factors such as contextual familiarity, accoustical characteristics of the room, distance between talker and listener, noise level, speech clarity, vocal effort, etc. As mentioned in the methodology section in Chapter IE, a known reference signal of 71 dB SPL was recorded prior to recording each speaker. The mouth to microphone distance also remained constant for each speaker. The white noise presented to each speaker under the noise condition remained constant at 75 dB SPL. All recordings were done in a sound treated audiological booth. The published speech stimuli were selected based on the objectives of this investigation. All speakers were English speaking males with no known articulation, language, or hearing defects.

By controlling for the above factors which may influence intelligibility, the results from the descriptive statistics show that all speakers were able to increase the intensity of their speech under the presence of noise. It was theorized that if speakers could increase the intensity of their voice and maintain this intensity above the background threshold noise level (75 dB SPL) then they should be heard and this would have a positive effect on the intelligibility of speech. To investigate the effects on intelligibility further, an indicator variable called cutdb was created. The actual intensity values from the sentence, key word, and vowel nucleus were used. A 1 was assigned to the indicator variable if all three variables of sentence, key word, and vowel nucleus were greater than 75 dB

SPL otherwise a 0 was assigned. The one indicator variable namely cutdbA used the principal component weighted values of greater than 75 dB SPL and the other indicator variable namely cutdb used the actual values from the sentence, key word, and vowel nucleus. All three intensity levels of the sentence, key word, and vowel nucleus had to be greater that 75 dB SPL.

The effect of intensity on intelligibility was tested in two separate models using general linear analysis. The only difference was the use of the indicator variable. One model used cutdb and the other model used cutdbA (as described above). The models included the log odds as the dependent variable and the independent variables of speaker type, noise condition, context predictability, and speaker nested within speaker type, the acoustical variables from the principal component indices which included fundamental ffequencypca, intensitypCa, voicingpCa, durationpCa,and ns, and the two-way interactions of noise condition with context predictability, speaker type with context predictability, speaker type with noise condition, cutdb with noise condition, cutdb with context predictability, cutdb with speaker type (substitute cutdbA for cutdb in the other model). Speaker type with noise condition was included in this model since it was significant in the logistic regression model described previously.

The results showed that the coefficients produced from each model were nearly identical when comparing the statistical outcome and there was not enough difference in quality of fit to choose either cutdb or cutdbA. Since there was no significant difference between the use of either indicator variable (cut dbA), it was decided that the composite acoustical variable of intensitypca from the principal component indices would be used in the final model, as this was consistent with the use of principal components for fundamental frequencypca, voicingpcg, durationpca,and ns

Although listeners was significant in the logistic regression model described earlier in the perceptual part of this study, this variable was not used in the final general linear model. All listeners were similar in that they were subjected to the same set of stimuli and had normal hearing; however, other listener characteristics were beyond the control of this investigator and were not the focus of this study.

With the alpha level set a priori at 0.05, a final model using general linear regression analysis was constructed. The model included log odds as the dependent variable with the following independent variables: speaker type, noise condition, context predictability, speaker nested within speaker type, intensitypca, fundamental frequencypCa, the two way interactions of speaker type with intensitypCa, fundamental frequencypCa with noise condition, intensitypCa with noise condition, noise condition with context predictability, speaker type with context predictability, and speaker type with noise condition.

The results of the final model using general linear analysis are summarized in

Table 43.

The results of the model presented accounted for 62% of the variance with a fairly small F-ratio for the degrees of freedom. Regression diagnostic statistics were calculated to ascertain that the variables did not have any wild values and that the relationship between the dependent variable and each of the independent variables were essentially linear. Residual values were plotted against predicted values and actual values and nothing was found to contradict the distributional assumptions of normality and homoscedasticity. Table 43. Summary of the General Linear Model of the effect of the acoustical variables (decibels, fundamental frequency mean ) on the perceptual variable (log odds correct).

Source df SS MS F Pr>F R-Sq

Model 39 6331.8205 162.3544 43.92 0.0001 0.62222

Error 1040 3844.3855 3.6965

Corrected Total 1079 10176.2060 126

The results of the analysis indicated significant effects for speaker type [F

(2,39) = 17.35, p = .0001], noise [F (1,39) = 386.79, p= .0001], predictability

[F (1,39) = 523.12, p = .0001], speaker nested within speaker type [F (24,39) = 5.87 , p = .0001], and intensitypCa [F (1,39) = 70.35, p = .0001. The following interactions were significant: intensitypCa by speaker type [F (2,39) =

4.46, p = .0118], fundamental ffequencypCa by noise [F (1, 39) = 11.96, p =

.0006], intensitypCa by noise condition [F (1, 39) = 22.69, p = .0001], noise condition by predictability [F (1, 39) = 5.20, p = .0228], and speaker type by predictability [F (2, 39) = 4.82, p = .0082].

Because speaker type by noise condition entered into the logistic regression model discussed previously, it remained in the general linear model, although the interaction was not significant [F (2,39) = 2.03, p = .1324]. The fundamental frequencypCa was also included even though it was not significant at the 0.05 level [F(l, 39) = 3.01, p = .0828]

Summary

It is not surprising to note that the main effect of speaker type was a predictor of logit correct. Examining the data from the logistic regression model and the descriptive statistics of intelligibility, the normal speakers were generally more intelligible than the two post surgical speaker groups; however, the two post surgical speaker groups' performance in intelligibility was very similar.

The similarity in intelligibility of the two post surgical speaker groups was not expected due to the different surgical approaches in removing the laryngeal carcinoma. One would suspect that between the two post surgical groups, the supraglottic speaker group would demonstrate greater intelligibility 127 since they still have both vocal folds following surgery. Examing the individual speaker's intelligibility means it was evident that among the speaker groups, the post surgical speakers demonstrated more variability within each group as compared to the normal speakers.

Noise as a main effect was a predictor of intelligibility. Based on the results from the logistic regression analysis and from the descriptive statistics of intelligibility, it appeared that the log odds of correctly identifying the key word declined in the presence of noise. The introduction of competing noise greatly decreased the intelligibility of all speakers regardless of context predictability.

The main effect of semantic contextual predictability was a predictor of intelligibility. Supporting this finding were the results from the logistic regression and descriptive statistics of intelligibility. Intelligibility was decreased when no semantic contextual cues were provided to the listener. This decline was seen for all speaker types regardless of the noise condition.

In summary, this investigator expected to see the main effects of speaker type, noise condition, and context predictability to emerge from the study due to the overall design of the investigation. The investigator predicted that normals would demonstrate more intelligibility overall and that intelligibility would decline in noise and that semantic contextual cues would aid the listener to correctly identify the key word.

Speaker nested within speaker type was a predictor of intelligibility. The descriptive statistic results showed that within each speaker group some speakers were more intelligible than others regardless of noise condition and contextual predictability, whereas some speakers were less intelligible under the same conditions. Within the normal speaker group, speaker 8 (Appendix E, Table 47) 128 appeared to maintain a higher level of intelligibility regardless of the noise condition and contextual predictability in comparison to speaker 5 whose intelligibility scores were the lowest under the presence of noise. Examining

Table 49 in Appendix E, speaker 1 of the supraglottic laryngectomy speaker group maintained a higher level of intelligibility regardless of the noise condition and contextual predictability, whereas speaker 6 exhibited lower intelligibility scores under the absence of noise and speaker 9 exhibited decreased intelligibility under the presence of noise. In Table 48, Appendix E, speaker 5 in the hemilaryngectomy speaker group exhibited the lowest intelligibility scores regardless of the noise conditions and contextual predictability conditions in comparison to other speakers within this speaker type. Speaker 9 of the hemilaryngectomy speaker group was able to preserve intelligibility regardless of the noise condition and contextual predictability. It is apparent that there was overlap among all three speaker groups due to the intraspeaker variability of each group. The composite acoustical variable of intensitypca was a main effect for intelligibility. IntensitypCa refered to the intensity of the speakers' signals. The overall vocal intensity level was a predictor of the logit correct. The log odds of correctly identifying the key word was increased when the speakers were able to speak louder. This can be best explained through the interaction effect of intensitypca by noise condition. Examination of the descriptive statistics demonstrated that all speaker groups exhibited a decrease in intelligibility under the presence of noise. Speakers who failed to increase their intensity level were generally less intelligible in the presence of noise. 129

The interaction of intensitypCa by speaker type was a predictor of intelligibility. Similar performance was noted for both the normal speakers and the supraglottic laryngectomy speakers on measurements of intensity for sentence, key word, and vowel nucleus. The overall means of intensity for the sentence, key word, and vowel nucleus for normal speakers as shown in Table

18 were, 74 dB SPL, 71 dB SPL, 74 dB SPL, and for supraglottic laryngectomy speakers intensity measures were 74 dB SPL, 70 dB SPL, and 73 dB SPL. In comparison, the hemilaryngectomy speakers' intensity for the sentence was 71 dB SPL, 68 dB SPL for the key word, and 70 dB SPL for the vowel nucleus. In general the hemilaryngectomy speakers differed from the normal speakers and the supraglottic speakers on intensity for the sentence, key word, and vowel nucleus. The results showed that the composite variable fundamental frequencypca was a predictor of intelligibility but only in the context of noise. The results from the descriptive statistics of acoustical measures demonstrated that overall fundamental frequency mean increased under the presence of competing noise and the logistic regression results showed a decrease in the log odds under the presence of competing noise. These results indicated that an increase in the fundamental frequency mean under the presence of competing noise decreased the log odds of correctly identifying the key word correctly for all speakers, but especially for the two post surgical speaker groups. This relationship was unclear, but it was speculated that this could be the result of inefficient transformation of the expired air for voicing secondary to the surgical alteration of the larynx leaving increased stiffness to the remaining tissues. 130

The results of the linear regression model showed that intensitypCa by noise condition was a predictor of intelligibility. It was evident from the descriptive statistics that all speakers were able to increase their intensity under the presence of noise. The odds of correctly identifying the key word were decreased under the presence of noise when speakers did not increased their vocal intensity above the background noise which was 75 dB SPL. In general the ability for speakers to adjust intensity is important in the presence of noise but not in the absence of noise.

The general linear model results showed an interaction of noise condition by contextual predictability as a predictor of the logit correct. This interaction was inherent to the stimuli used and design of this investigation. The log odds of correctly identifying the key word increases in the absence of noise and when contextual cues are given. All speaker groups appeared to adjust under the presence of noise when contextual cues were given and also in the absence of noise when no contextual cues were presented, however, the log odds significantly decreased in the presence of noise when no contextual cues were given. The investigator expected this type of interaction to occur. Examining the descriptive statistics the overall intelligibility mean was 96.1% in the no noise high predictability condition and 72.8% in the no noise low predictability condition. The overall intelligibility mean in the noise high predictability condition was 73.7% and 38.8% in the noise low predictability condition.

The general linear model results also showed an interaction of speaker type by context predictability as a predictor of the logit correct. The descriptive statistics for intelligibility and the logistic regression results showed that all speaker groups preserved intelligibility well when semantic contextual cues were 131 presented, however, the log odds were greater for the normal speaker group.

The lack of semantic contextual cues greatly affected intelligibility in all speaker groups but more so for the post surgical speaker groups. As displayed in Table

4, the overall mean intelligibility under the high predictability condition was 95% for the normal speakers, 82% for the supraglottic laryngectomy speakers, and

76% for the hemilaryngectomy speakers. Under the low predictability condition the overall intelligibility means were 64% for the normal speakers, 52% for the supraglottic speakers, and 53% for the hemilaryngectomy speakers.

Overall Interpretation of Intelligibility

In summary the results of this investigation indicated that normal speakers were more intelligible overall and also demonstrated the least speaker variability.

The post surgical speaker groups performed essential equal to the normal speaker group under the absence of noise regardless of contextual predictability.

Under the presence of noise, the post surgical speaker groups exhibited similar log odds for correctly identifying the key word. There was considerable variation from speaker to speaker displayed in the post surgical speaker groups.

Although the speakers were able to adjust in the noise condition, the presence of noise decreased the log odds of correctly identifying the key word for all speaker groups. The presence of contextual cues aided in increasing the log odds of correctly identifying the key word. On the other hand, the combination of the presence of noise and no contextual cues greatly decreased the log odds for intelligibility. The effects of intensitypca on the identification of the key word demonstrated that all normal speakers were able to increase their vocal intensity 132 above the level of the background noise to preserve intelligibility, whereas five of the nine speakers for the supraglottic speaker group increased their vocal intensity and only three of the nine speakers did for the hemilaryngectomy speaker group. The ability to increase vocal intensity was very important in the correct identification of the key word in the presence of noise but not in the absence of noise.

The normal speaker group did better with the use of contextual cues regardless of the noise condition. Providing contextual cues did aid the post surgery speaker groups in the log odds of correctly identifying the key word in the noise condition but noise affected intelligibility since these two groups did better in the absence of noise when no contextual cues were presented. The interaction of fundamental ffequencypCa by noise condition demonstrated that an increase in fundamental frequency in the presence of noise was associated with a decrease in the log odds of correctly identifying the key word.

The following were the majors findings of this investigation regarding the purposed initial research questions found in Chapter I.

1. Does alteration of the larynx via vertical partial laryngectomy or horizontal partial laryngectomy produce a predictable effect on intelligibility of speech as a function of the presence or absence of competing background noise (75 dB SPL white noise). The effects of the independent variables on the log odds of correctly identifying the key word in the sentences revealed that all speaker groups displayed a reduction in the estimated log odds under the presence of competing noise. The decline in intelligibility was less for the normal speaker group than for the two post surgery speaker groups. Alteration of the larynx did 133 indeed produce a predictable decline in intelligibility when noise was introduced.

Examination of the individual speaker results within the vertical partial laryngectomy speaker group and within the horizontal partial laryngectomy speaker group revealed variability among the speakers. This speaker variability affected each post surgery speaker group Some speakers were more intelligible than others regardless of the noise condition.

This may be due to the extent of surgical involvement to remove the laryngeal carcinoma. In examining the information which was collected from the medical charts of the individuals from each surgical group, Appendix G, Table

74, speakers 6 and 9 from the supraglottic speaker group were individuals whose performance decreased in the presence of noise and they also seemed to have more involved surgery. Both of these individuals underwent a radical neck dissection, partial resection of the tongue, and a pectoralis myocutaneous flap for reconstruction. These individuals also received radiation treatments following surgery. In Table 74, Appendix G speaker 5 was the worst speaker for the hemilaryngectomy speaker group in all conditions. This speaker was the oldest speaker with the greatest lost of hearing allowable to qualify for this study. He had also received a teflon injection in an area that was resected. Teflon is a substance that is injected into the tissue which bulks up the area to provide for a better glottic closure. Once teflon is injected into the tissue the area becomes stiffer and does not vibrate but remaining tissue around in the glottal area does vibrate. The other hemilaryngectomy speakers who did poorly in the noise conditions were speakers 1, 3 and 4. A commonality which existed in speakers

1 and 3 was the that surgery involved the anterior commissure. Speaker 4 had 134 just the left vocal cord removed and did not differ from others within that group.

Why this speaker's performance was poorer in noise is unexplainable.

In general, individuals who were not able to increase the signal-to-noise ratio adequately to preserve intelligibility affected the performance of the overall speaker group. The anatomical and physiological changes that occur following removal for laryngeal carcinoma seemed to have affected intelligibility and restricted some of the subjects in their ability to increase intensity when background noise was present.

The findings from this investigation showed how closely related the two post surgical speaker groups performed under the noise conditions.

Conventional wisdom would predict that individuals with a vertical partial laryngectomy would be have the greatest decline in intelligibility regardless of the noise condition. The extent of surgery for removal of tissue in these patients varies from patient to patient and does involve the removal of a vocal fold or at least the vibrating part of a vocal fold and sometimes the removal of one vocal fold and part of the other vocal fold. Those individuals who undergo a horizontal partial laryngectomy on the other hand, have both vocal folds intact therefore leaving the true vocal folds to vibrate when speaking.

2. Does alteration of the larynx via vertical partial laryngectomy or horizontal partial laryngectomy produce a predictable effect on intelligibility of speech as a function of the strength of the contextual cues provided within the stimulus sentences (SPIN Test high and low predictability sentences)? This finding was expected and reflected the stimuli used in this investigation. The use of contextual information aided all speaker groups and increased the log odds of 135 correctly identifying the key word. In the high predictability sentences the final key word is predictable from the context, whereas, in the low predictability sentences the final word cannot be predicted from context. The high predictability sentence, therefore, allows for a greater likelihood of correct identification of the final key word.

The results showed that the log odds of correctly identifying the last word in the sentences were affected by the independent variables of speaker type and context predictability. The likelihood of identifying the last word correctly greatly increased for the normal speaker group. This indicates that listeners did use the semantic contextual cues and accurately identified the key word more so for the normal speaker group than the two post surgical speaker groups.

3. Does alteration of the larynx via vertical partial laryngectomy or horizontal partial laryngectomy produce a predictable effect on intelligibility of speech as a function of the interactive effects of competing background noise and the strength of contextual cues? The observations that emerged from this study showed that both noise condition and context predictability did have a predictable effect on the intelligibility of speech for all speaker groups. Listeners used semantic contextual cues when no noise was present but with the introduction of noise the log odds for correct identification of the key word decreased. The interactive effects of competing background noise and no semantic contextual cues were associated with poorer identification of the key word in all speaker groups; however, this combination had the greatest effect on the post surgical groups. The listener's likelihood of identifying the key word correctly in this combination was essentially equal for both post surgical speaker groups and the 136 results showed a severe decrease in the log odds of correctly identifying the key word. This was probably due to the inability of some speakers within each group to increase the signal above the level of background noise.

4. What selected acoustical features (vocal fundamental frequency, vocal intensity, segment duration, and percentages of voicing) help in predicting intelligibility of speech among vertical partial laryngectomees, horizontal partial laryngectomees, and normal speakers as a function both of competing noise in the speaking/listening environment and of the strength of contextual cues. The results from this study showed that the main effect of vocal intensity (intensitypca) was a predictor of intelligibility for all speaker groups. It is known that one speaks more loudly in the presence of noise to try and preserve the intelligibility of speech; however, studies have shown that there is a reduction of speech intensity for sustained vowel phonation in hemilaryngectomy speakers (Hirano, et. al., 1987; Leeper, et. al., 1990). This investigation has shown, which has not be documented in the literature, that although individual speaker differences exits, the two post surgical speaker groups were able to increase the intensity of their speech under the presence of noise but their capabilities were limited and the resultant increase was not enough to produce a favorable signal-to-noise ratio. The investigator noted that at the time of data collection, some of the post surgical speakers appeared to be talking at their maximum possible vocal effort in the absence of noise and appeared to have little capacity to increase their vocal effort in the presence of noise. Their vocal effort; therefore, was only minimally changed under the presence of noise.

Examination of the results in Appendix F, Tables 62 and 64 revealed that the 137 hemilaryngectomy speakers 4 and 5 were able to increase their intensity very little under the presence of noise. In Appendix F Tables 70 and 72 showed that speaker 5 for the supraglottic laryngectomy speakers also displayed limited ability to increase intensity under the noise conditions. The interaction of intensitypCa by speaker type was a predictor of intelligibility. The post surgical speaker groups were not able to increase the intensity of their speech in comparison to the normal speakers. It is speculated that the anatomical and physiological restrictions secondary to the surgical procedures undergone by these individuals places limitations on the laryngeal structure in combination with the aerodynamics of the entire system preventing these individuals to sustain a higher intensity for a given period of time. The video findings by Blaugumd, et. al. (1984) taken on individuals who have undergone a vertical partial hemilaryngectomy suggests voicing in these individuals is due in part to "sphincterization and compensatory hypertrophy of glottic and supraglottic remnants" (page 311). Which means that whatever structures and tissues remain after surgery constrict and are set into vibration as air passes through the glottic area. The restriction of movement in the remaining tissues places a limitation on the amount of air that can go through the area causing a decrease in the ability to increase intensity The interaction of intensitypCa by noise condition was a predictor of intelligibility. Examining the results showed that all speakers were able to increase the intensity of their speech in the presence of noise. This finding suggests that the group of speakers who were able to increase the signal-to-noise ratio were more intelligible than those who were unable to raise vocal intensity but only under the presence of noise. At other times there was no such effect. 138

The interaction of fundamental frequencypca mean by noise condition was a predictor of intelligibility. In examining the data the results showed an increase of fundamental frequency under the presence of noise for all speaker groups.

The results have shown that the two post surgical groups have a decrease in intelligibility under the presence of noise. Black (1961) reported that as vocal intensity increases fundamental frequency increases in normal speaking young adult males. This finding from the literature showed what happened to normal speakers as they increase intensity. Perhaps what happened to the two post surgical groups in this study was that in the process of trying to increase vocal intensity under the presence of noise, fundamental frequency increased; but the speakers were unable to increase intensity to the degree to increase the log odds of correctly identifying the key word. The valving of the vocal folds or pseudo vocal folds may restrict the post surgical speakers ability to increase vocal effort.

What may happen is that in the attempt to increase intensity additional muscle constriction occurs causing increase tension of the remaining tissues resulting in a higher fundamental frequency. CHAPTER V

SUMMARY AND CONCLUSIONS

The purpose of this study was to investigate the effectiveness with which

two groups of individuals who have undergone either a vertical partial hemilaryngectomy or a horizontal partial laryngectomy preserve the intelligibility of their speech under two conditions of noise: no noise and 75 dB SPL of white

noise. Randomly selected SPIN test sentences were used. Half of the sentences contained no semantic contextual cues and half of the sentences did contain

semantic cues to aid in intelligibility. In addition to the intelligibility investigation, this study also examined the acoustics of the speech samples to see

what variables help in predicting intelligibility among the speaker groups.

Everyday environmental speaking conditions can place a speaker and

listener in a variety of background noises and these background noises may

effect the intelligibility of the speech signal. This investigator looked at the

intelligibility of speakers under the absence of noise and also under the presence

of 75 dB SPL white noise. Both the speaker and the listener were subjected to

the same known noise conditions.

The results of this in vestigation demonstrated that the two post surgery

speaker groups were very similar to each other in comparison to normal

laryngeal speakers in intelligibility. It was also demonstrated that in the absence

139 140 of noise the two post surgical speaker groups were similar to normal laryngeal speakers in intelligibility. It was apparent that all individuals made modifications in the presence of noise and attempted to increase the intensity of their voice.

Speaker variability was evident in all speaker groups but more variability was noted within the post surgical speaker groups. Speaking in the presence of noise greatly affected all speaker groups but more so for the post surgical speaker groups. Semantic contextual cues aided all speaker groups regardless of the noise condition.

Implications for Clinical Use

Studies have reported less than desirable voice quality from individuals following laryngeal surgeries (Hirano; 1981, Blaugrund, et. al., 1984; and

Logemann, 1985). A more important clinical issue from this investigation addressed how intelligible the post surgical speakers were in the absence of noise and under the adverse condtion of noise. The results of this study showed that the post surgical speakers were not as intelligible in comparison to normal speakers and that in certain environments where there was an increase in noise with no contextual cues provide their intelligibility declined.

It is felt, by this investigator, that individuals who have undergone either a partial hemilaryngectomy or a supraglottic laryngectomy should be seen for a voice evaluation preferably before surgery and following surgery. This research supports rehabilitative speech training for individuals who have difficulty with intelligibility following a partial laryngectomy. Individuals should be advised to simplify the speech context in the presence of noise. Although this study did not address visual cues obtained from the speakers to aid listeners, it is theorized that head orientation and facing the listener would improve visual articulatory cues and probably would improve intelligibility even in adverse noise conditions.

Further research is needed in this area.

Suggestions For Future Research

The results of this investigation indicate that vertical partial laryngectomy speakers and horizontal laryngectomy speakers are not as different from each other as conventional wisdom would suggest. These types of speakers are significantly different from normal laryngeal speakers, but not from each other.

In general this investigation represented a small segment of the population who have undergone conservation laryngeal surgeries. From this study it was shown that intra speaker variability existed within speaker group Individuals who have more involved surgeries may be less intelligible and less able to preserve intelligibility in adverse speaking conditions. Further investigation is needed to analyze perceptual and acoustical differences arrising from the different surgery techniques, e.g. hemilaryngectomy surgeries. Although it was not the focus of this study, it was evident from the surgical information taken from the patients' medical charts that those speakers who demonstrated greater intraspeaker variability were individuals who had more involved surgery.

The design of this study addressed white male speakers which limits the ability to generalize. Further studies should incorporate female speakers and minorities and compare the intelligibility and acoustical parameters among the speakers.

The results of this study demonstrated that all speakers made adjustments in the presence of noise to preserve intelligibility. A follow up study should investigate the effectiveness of these adjustments to evaluate if the adjustments made by the speakers actually improved intelligibility or hindered intelligibility. 142 It is suggested that the same speech signals be played to listeners without the noise present. The information gained from this would tell if the adjustments made be the speakers were either effective or ineffective by adding to the speech signal or degrading the signal.

The use of advanced computer technology and digital signal processing software allows for effective comparative acoustical analysis of normal and pathological voices as this investigation has demonstrated. With this capability at hand the nature of speech and intelligibility can be studied thoroughly. With modem analytic techniques a speech signal can be digitized and real tme analysis can be conducted on a monitor. As seen in this investigation the waveform can be displayed and edited along with viewing the spectrogram while simultaneously hearing the segmented speech signal This capability allows for easier, faster, and more accurate measuresments by moving cursors on the screen. As shown in this investigation, quite accurate and high reliability resulted from two independent investigators marking the same speech segment.

This supports that larger amounts of data can be analyzed over a shorter period of time. The use of data gained from this technology can be very useful in the diagnosis and treatment of laryngeal diseases and the objective evaluation of surgical techniques. APPENDIX A

SPEAKER INFORMATION

143 Table 44. Normal speaker information for age and three frequency average (in dB HL) for right and left ear.

NORMAL AGE 3 FREQUENCY SPEAKER YRS:MOS AVERAGE RIGHT/LEFT dB HL

1 39:11 25/25

2 73:08 25/25

3 65:01 25/25

4 55:10 25/25

5 67:06 25/25

6 60:05 25/25

7 51:08 25/25

8 63:01 25/28

9 58:07 25/25 145

Table 45. Supraglottic laryngectomy speaker information for age three frequency average (in dB HL) of right/left ear, time since surgery, and stage of cancer at time of surgery.

SUPRAGLOTTIC LARYNGECTOMY SPEAKERS

3 FREQUENCY SUBJECT AGE AVERAGE TIME SINCE STAGE OF YRS:MOS RIGHT/LEFT SURGERY CANCER AT dB HL TIME OF SURGERY

1 43:00 25/25 2mo3days T2NOMO STAGE II

2 64:02 62/30 9molday unknown

3 55:05 25/27 9mo24days T2 NO M0 Stage II

4 66:07 25/43 lmo21days T2N0M0 Stage II

5 50:03 25/25 lyr3mol 6days T2N0M0 Stage II

6 64:04 27/23 2yr4mo22days T2N2MO Stage IV

7 58:07 25/27 lyr7mo25days unknown

8 49:01 25/25 3yr7mol 3days T2N2M0

9 54:07 23/2 8yr8mo22days T3N2AM0 Stage IV 146

Table 46. Hemilaryngectomy speaker information for age three frequency average (in dB HL) of right/left ear, time since surgery, and stage of cancer at time of surgery.

HEMILARYNGECTOMY SPEAKERS

3 FREQUENCY SUBJECT AGE AVERAGE TIME SINCE STAGE OF YRS:MOS RIGHT/LEFT SURGERY CANCER AT dB HL TIME OF SURGERY

1 65:03 32/25 2mo20days T2N0M0 Stage II

2 43:03 25/25 2yr3mo0days T1N0M0 Stage I

3 54:08 25/25 9mol0days T1BN0M0 Stage I

4 64:06 25/25 4yrlmo8days unknown

5 78:11 42/35 6yrl0mo2days unknown

6 67:01 25/27 4yrl lmo6days unknown

7 61:11 25/25 2yr3mol6days unknown

8 60:06 25/25 4yr4mo29days T1NOMO

9 61:11 25/25 3yr6mol3days unknown APPENDIX B

SPEAKER’S CONSENT TO INVESTIGATIONAL PROCEDURE

147 148

THE OHIO STATE UNIVERSITY Protocal No. 83B0171

Consent to Investigational Procedure I would like to thank you for volunteering for this study. The purpose of this form is to inform you about my study, its goals, and an explanation of the tasks that you will be performing. The main goal of this study is to improve rehabilitation for people who have a speech or communication problem due to treatment for cancer of the head and neck. I will be investigating adjustments made by speakers under various noise conditions. I will compare the speaking skills of individuals who have undergone either a partial laryngectomy, or a supraglottic laryngectomy with normal laryngeal speakers. To allow me to compare speaking skills, I will need to record your voice onto audio tapes using a microphone positioned seven inches from your mouth. I will ask you to perform various speaking tasks. 1. You will read a 98 word reading passage at your most comfortable level, and 2. You will read 20 randomly selected sentences from the Speech Perception In Noise Test that will be given under different noise conditions. You will hear the noise through headsets. The anticipated duration of this recording will take approximately 20 minutes.

Consent I hearby acknowledge that Bernice K. Gerdeman, M.A. or Michael D. Trudeau, Ph.D. have provided information about the procedure described above, and about my rights as a subject, and that any questions I have had have been answered to my satisfaction. I understand that I may contact Bernice K. Gerdeman if I have additional questions. I understand that my participation will remain confidential. I understand that I am free to withdraw my consent and participation in this project at any time without prejudice to myself. I have read and fully understand the consent form. I sign it freely and voluntarily. A copy has been given to me.

Date:______Time:______Type:______No.______Signature of the Subject:______Witness: ______I certify that I have personally explained this form to the subject before requesting the subject to sign it. Signed: ______(Bemice K. Gerdeman or Authorized Representative) APPENDIX C

INSTRUCTIONS FOR LISTENERS AND RESPONSE FORMS

149 150

INSTRUCTIONS FOR LISTENERS

Thank you for participating in this study. Your information will help design more effective rehabilitation programs for individuals who have undergone surgical treatment for cancer of the larynx. Please answer the following questions, then read the directions. 1. N am e:______2. A ge:______S ex: ______Native Language:______3. Do you have a hearing impairment: ______4. Are you familiar with speakers who have had all or part of their voice box removed? ______

You will listen to 54 speakers reading 20 sentences each.. Your task is to write the last word of each sentence in the blanks below. There is enough time between each sentence to allow you to write your response on the line. Sometimes the last word of the sentence will be predictable, e. g. "The flag is red, white and blue". Sometimes the last word of the sentence will not be predictable, e.g. "They were talking about the book". You should guess what the word is if you are uncertain of it or did not hear it clearly. Please put your best guess in every blank. If you have absolutely no idea what the speaker said, put an X on the line. If you have any questions or lose your place press stop on the tape cassette and I will assist you. Before you hear the 20 sentences of each speaker, you will hear the speaker read the following two sentences to acquaint you with their voice: "The rainbow is a division of white light into many beautiful colors. These take the shape of a long, round arch with its path high above and its two ends apparently beyond the horizon". 15 1 You will hear speakers in two different conditions; speaking in a quiet background and speaking in a noisy background. When the speaker is speaking in a quiet background you will hear the two rainbow sentences above followed by the 20 sentences. When the speaker is speaking in a noisy background you will hear the two rainbow sentences above, followed by the noise with no sentences and then followed by the 20 sentences mixed with background noise. Please listen carefully and write down the last word the speaker says in each sentence.

The following is a practice session.

1. 6 .. 2 . 7._ 3. 8._ 4. 9._ 5 . ______10.______

Hearing screening:

250 500 IK 2K 4K

R ______L ___

Three frequency average:

R ______L 152

Speaker 1

1 .______6. ______l l . ______16.. 2 .______7.______12.______17., 3 .______8.______13.______18., 4 .______9.______14.______19, 5 .______10.______15. ______20,

Speaker 2

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 3 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 153

Speaker 4

1. 6. 11. 16, 2 .______7.______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15. ______20,

Speaker 5 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 6 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17,

3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 154

Speaker 7

1. 6. 11. 16.. 2 .______7.______12.______17.. 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15. ______20,

Speaker 8 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 9

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 155

Speaker 10 (noise)

1. 6. 11. 16, 2 .______7.______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15. ______20,

Speaker 11 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 12

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19,

5 .______10.______15.______20, 156

Speaker 13 (noise)

1. 6. 11. 16.. 2 .______7. ______12.______17.. 3 .______8.______13.______18., 4 .______9.______14.______19., 5 .______10.______15.______20.

Speaker 14

1. 6. 11. 16, 2 .______7.______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15. ______20,

Speaker 15 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 157

Speaker 16

1. 6. 11. 16.. 2 .______7. ______12.______17., 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 17 (noise)

1. 6. 11. 16, 2 .______7.______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5. ______10.______15. ______20,

Speaker 18

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19,

5 .______10.______15.______20. 158

Speaker 19 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 20 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 21 (noise)

1. 6. 11. 16, 2 .______7.______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 . ______10.______15. ______20, 159

Speaker 22

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 23 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4. ______9.______14.______19, 5 .______10.______15.______20,

Speaker 24 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 160

Speaker 25

1. 6. 11. 16. 2 .______7. ______12.______17. 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 26

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 27

1. 6 . 11. 16 , 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19,

5 .______10.______15.______20, 161

Speaker 28 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 29

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 30 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 162

Speaker 31 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 32

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 33

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 163

Speaker 34

1. 6. 11. 16. 2 .______7. ______12.______17.. 3 .______8.______13.______18. 4 .______9.______14.______19, 5 .______10.______15.______20.

Speaker 35 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20.

Speaker 36 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20. 164

Speaker 37 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 38

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 39

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20. 165

Speaker 40

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 41

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 42

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 166

Speaker 43

1. 6 . 11. 16 . 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 44

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 45 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17,

3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 167

Speaker 46 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 47 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 48

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 168

Speaker 49 (noise)

1. 6. 11. 16.. 2 .______7. ______12.______17.. 3 .______8.______13.______18., 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 50

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 51 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20, 169

Speaker 52 (noise)

1. 6. 11. 16.. 2. ______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 53 (noise)

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20,

Speaker 54

1. 6. 11. 16, 2 .______7. ______12.______17, 3 .______8.______13.______18, 4 .______9.______14.______19, 5 .______10.______15.______20. APPENDIX D

LISTENER S CONSENT TO INVESTIGATIONAL PROCEDURE

170 171

The Ohio State University Protocol No. 83B0171

Consent to Investigational Procedure

I, ______, hereby authorize Bernice K. Gerdeman, M. A. to perform the following procedure. I will provide the judgement of how intelligible or understandable various speakers (hemilaryngectomees and supraglottic laryngectomees) are by identifying words spoken by each speaker and writing my response on the form provided. The stimulus for this task is a tape recorder and I will be hearing the speakers through headsets. The experimental portion of the treatment are my responses to the various speakers' speech. This research is done as part of an investigation entitled: "Preservation of Intelligibility and Acoustical Characteristics in Partial Laryngectomees and Normal Laryngeal Speakers Produced Under Conditions of Competing Noise".

1. The purpose of this procedure is to investigate speech intelligibility/understandability of partial laryngectomees to normal laryngeal speakers in a quiet condition and in a noise condition.

2. The goal of this study is to improve rehabilitation of people who have a speech or communication problem due to treatment for cancer of the head and neck.

3. The anticipated duration of the procedure for each subject is 3 hours. It is necessary to break this listening session into two separate 1 1/2 hour sessions.

I hereby acknowledge that Bernice K. Gerdeman, M.A. has provided information about the procedure described above, about my rights as a subject , and that any questions I have had have been answered to my satisfaction. I understand that I may contact Bernice K. Gerdeman should I have additional questions. She has explained any risks involved and I understand them; she also has offered to explain all possible risks or complications. 172 I understand that, where appropriate, the U.S. Food and Drug Administration may inspect records pertaining to the study. I further understand that records obtained during my participation in this study may be made available to the sponsor of this study and that the records will not contain my name or other personal identifications. Beyond this, I understand my participation will remain confidential. I understand that I am free to withdraw my consent and participation in this project at any time after notifying the investigator without prejudicing future care. No guarantee had been give me concerning this procedure. I have read and fully understand the consent form. I sign it freely and voluntarily. A copy has been given to me.

Date:______Tim e:______Signed:______Listener

W itness:______I certify that I have personally explained this form to the subject before requesting the subject to sign it.

Signed:______Bernice K. Gerdeman, M.A. APPENDIX E

MEAN AND STANDARD DEVIATIONS FOR EACH INDIVIDUAL SPEAKER GROUP

173 TABLE 47. Descriptive statistics (Mean\Standard Deviation) from the percentage correct for normal speakers in the no noise-high predictability condition, no noise-low predictability condition, noise-high predictability condition, & noise-low predictability condition.

Speaker No Noise-High - No Noise - Low Noise - High Noise - Low Predictability Predictability Predictability Predictability

Normal 1 99.36\1.36 87.10S21.51 98.39S03.13 57.10S35.14 Normal 2 98.57S4.30 74.78S35.57 92.96S09.98 41.58S41.45 Normal 3 97.49\3.13 76.25S23.94 98.71S02.26 62.90G2.16 Normal 4 93.55S8.74 52.58S18.19 90.0CM2.40 49.68S30.04 Normal 5 96.77S4.30 74.19S31.28 79.35S21.84 36.77S30.27 Normal 6 98.92N2.28 70.97S26.76 90.00S16.69 37.74S20.18 Normal 7 98.39M.70 58.71S37.68 98.7 ISO 1.67 55.48S31.45 Normal 8 99.68S1.02 97.74S04.04 96.13S08.30 65.48S39.48 Normal 9 98.53S2.22 77.06S27.06 98.39S05.10 67.42S25.47 TABLE 48. Descriptive statistics (MeanXStandard Deviation) from the percentage correct for the hemiiaryngectomy speakers in the no noise-high predictability condition, no noise-low predictability condition, noise-high predictability condition, & noise-low predictability condition.

Speaker No Noise-High - No Noise - Low Noise - High Noise - Low Predictability Predictability Predictability Predictability

Hemi 1 98.92S01.61 79.77X18.59 46.33X35.29 02.51X04.20 Hemi 2 98.53S01.68 65.95X36.54 76.13X25.90 28.06X29.65 Hemi 3 95.7004.27 61.58S24.84 39.3CX31.73 06.09X11.79 Hemi 4 91.4008.83 75.95X31.35 12.26X14.81 02.26X05.05 Hemi 5 83.87V20.79 35.81X38.00 03.94X08.50 02.05X06.81 Hemi 6 99.03N01.56 85.16S21.35 86.77X17.30 50.97X37.95 Hemi 7 90.32X15.47 70.97S29.18 82.9022.71 63.55X37.00 Hemi 8 95.16S10.87 84.52X22.18 86.77S23.58 73.87X23.92 Hemi 9 98.92V01.61 90.03X19.38 91.61X09.52 59.68X26.96 TABLE 49. Descriptive statistics (MeanXStandard Deviation) from the percentage correct for supraglottic laryngectomy speakers in the no noise-high predictability condition, no noise-low predictability condition, noise-high predictability condition, & noise-low predictability condition.

Speaker No Noise-High - No Noise - Low Noise - High Noise - Low Predictability Predictability Predictability Predictability

Supra 1 99.35X01.36 84.52X33.79 94.19^09.71 50.00X38.72 Supra 2 92.47X17.89 78.59X31.25 71.61X25.44 35.81X31.66 Supra 3 97.49N04.50 58.36v40.56 68.39X26.20 38.71X28.33 Supra 4 94.27X05.77 71.55X29.03 57.48X25.76 18.28X22.98 Supra 5 97.49X06.41 80.06X25.64 65.16X31.67 28.06X28.57 Supra 6 86.45X17.59 47.42X33.11 53.41X24.99 15.25X19.68 Supra 7 99.64X01.08 88.2A15.01 71.26X27.27 43.01X35.78 Supra 8 99.35X01.36 77.42X19.83 89.03X15.96 39.68X28.17 Supra 9 94.52X10.87 56.45X29.65 47.10X26.43 12.90X11.97 APPENDIX F

DESCRIPTIVE STATISTICS FOR THE DEPENDENT ACOUSTICAL VARIABLES BY EACH SPEAKER

177 TABLE 50. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL)of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for normal speakers in the no noise-low predictability condition.

Speaker dB senfsS.D. dB wordXS.D. dB nucXS.D. sent duiXS.D. wd duriS.D. nuc duiXS.D.

Norm 1 72.3X2.1 67.7X3.6 71.5X3.8 1750.9X210.8 481.6^083.3 172.3X071.5 Norm 2 72.4X1.4 70.7\1.6 74.2X2.1 2282.0X336.6 582.7^089.3 206.7X055.2 Norm 3 71.9X2.0 67.4X3.1 70.8X4.1 1995.1X253.1 489.0X106.8 163.9X038.4 Norm 4 68.0x2.0 66.1X2.2 69.4X2.4 2274.5X299.0 sus'oesj 160.8X030.2 Norm 5 69 .CM.7 66.2X2.7 70.7X3.6 2247.7X352.1 536.1X078.6 145.9X057.6 Norm 6 71.6X1.1 65.7X2.4 69.8X3.2 2020.CN235.5 485.4X111.2 147.6X034.6 Norm 7 70.1N1.2 66.9X1.6 70.6X1.7 1646.1X161.7 497.2X072.1 144.0X047.0 Norm 8 75.4X2.0 74.7X3.1 78.6X2.2 1737.9X172.0 534.9X076.0 191.1X100.6 Norm 9 70.CM.9 65.6X3.0 68.8X2.7 1759.7X158.0 467.3X119.5 139.6X037.3 TABLE 51. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for normal speakers in the no noise-low predictability condition.

Speaker sf meanXS.D. wf meanXS.D. nf meanXS.D. sent voicXS.D. wd voicXS.D. nuc voicXS

Norm 1 130.4X9.4 113.8X09.8 111.3X10.2 52.3X08.8 39.7X21.4 83.3X19.7 Norm 2 107.8X2.2 096.5MJ3.4 095.2X05.4 64.8X06.4 50.9X09.5 95.7X10.2 Norm 3 089.7X3.0 081.9X06.6 079.7X07.2 49.4X07.6 42.7X16.4 84.2X15.9 Norm 4 088.8X2.7 088.1X06.9 087.1X07.2 54.9X07.9 52.0X12.2 98.5X04.9 Norm 5 120.5X4.1 118.7X10.6 117.1X11.1 56.0X04.9 31.5X16.0 79.3X22.3 Norm 6 132.1X2.3 117.6X09.8 116.7X10.1 56.2X07.0 29.9X14.8 68.9X16.2 Norm 7 101.1X2.4 091.3X05.4 087.2X06.4 58.8X05.6 42.4X10.2 89.5X13.7 Norm 8 141.4X2.0 130.1X15.9 125.1X16.2 60.1X07.9 46.9X19.5 88.5X15.3 Norm 9 106.7X4.1 100.1X11.9 096.0X09.8 53.4X10.1 43.2X13.9 73.2X19.0 TABLE 52. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL)of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for normal speakers in the no noise-high predictability condition.

Subject dB sentXS.D. dB wordXS.D. dB nucXS.D. sentdutXS.D. wd duiXS.D. nuc duiXS.D.

Norm 1 72.2M.4 65.2X2.3 68.3X1.9 1856.5X165.2 476.8X086.0 143.3X045.1 Norm 2 73.2X2.0 71.2X2.6 74.7X2.9 2337.2X274.5 620.2X104.5 171.3X029.7 Norm 3 73.2X2.0 67.3X2.8 71.2X3.7 1958.0M52.2 490.3X055.4 137.7X037.7 Norm 4 68 .CM .3 64.0X2.3 67.8X1.8 2268.3X233.6 541.6X108.3 156.1X043.0 Norm 5 68.5X1.3 64.2X3.6 65.8X4.2 2249.1X272.5 523.4X076.3 173.7X051.4 Norm 6 73.1X1.4 66.5X2.0 67.1X3.4 2081.6X276.8 452.4X100.2 140.4X027.9 Norm 7 72.0X1.3 68.1X1.9 71.1X2.0 1695.6X175.2 471.9X068.4 180.9X040.5 Norm 8 74.9X1.6 73.7X2.8 77.0X2.4 1858.6X154.5 514.4X077.6 205.0X104.2 Norm 9 70.6X1.9 64.3X2.6 68.4X2.1 1843.9X263.5 495.1X104.8 159.7X073.2 180 TABLE S3. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for normal speakers in the no noise-high predictability condition.

Subject sf meanXS.D. wf meanXS.D. nf mean\S.D. sent voicXS.D. wd voicXS.D. nuc voicXS.D.

Norm 1 135.4X9.8 113.9X16.9 110.6X18.5 48.6X07.9 27.6X14.4 61.6X19.2 Norm 2 107.7X3.8 095.1X03.4 093.1X05.3 76.1X11.5 62.9X14.9 99.5X01.5 Norm 3 089.1X2.7 082.5X02.2 080.8X06.4 52.6X07.8 34.0x12.9 79.8X19.9 Norm 4 088.4X1.7 087.7X06.9 085.0X03.8 56.1X09.2 48.6X20.7 98.7X04.2 Norm 5 117.5X3.1 105.8X09.6 095.2X34.8 61.6X09.4 45.0x21.3 81.3X31.4 Norm 6 133.9X5.1 116.8X05.2 107.8X09.9 63.1X07.2 37.7X13.9 56.4X23.2 Norm 7 104.4X5.3 089.9X06.3 088.5X08.1 64.5X08.5 49.3X08.9 92.3X07.9 Norm 8 136.4X6.3 116.1X06.2 119.3X14.4 64.2X09.0 61.4X18.2 90.5X12.2 Norm 9 106.9X5.0 097.1X11.1 095.0X11.6 53.9X12.7 33.8X22.2 73.2X19.3 TABLE 54. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for normal speakers in the noise-low predictability condition.

Subject dB seniNS.D. dB worthS.D. dB nucXS.D. sent duiXS.D. wd dui\S.D. nuc duiXS.D.

Norm 1 77.9X2.1 74.5X2.7 76.5X3.7 1900.0X305.2 499.8X034.7 159.3X067.2 Norm 2 76.0\2.6 75.2X4.2 77.8X4.3 2395.9X450.1 603.2X108.3 283.^058.2 Norm 3 78.7X1.6 75.0X3.4 79.0X3.0 2272.5X297.0 550.5X076.2 162.3X048.4 Norm 4 76.1X1.6 74.3X2.1 78.1X1.8 2367.2X323.0 528.2X123.1 174.7X061.2 Norm 5 75.9X1.7 72.5X2.4 74.7X2.9 2580.5X250.6 626.9X096.4 168.2X038.0 Norm 6 79.4X0.9 75.6X1.8 78.9X1.8 2027.5X389.2 466.9X129.4 200.8X111.1 Norm 7 77.0x1.5 73.9X2.3 76.6X2.3 1746.7X292.7 495.1X147.8 178.3X039.7 Norm 8 77.5X1.7 76.6X2.7 80.3X2.9 1839.1X343.4 514.2X058.4 190.4X076.6 Norm 9 76.3X1.4 74.5X2.4 77.2X3.2 1830.8X378.9 478.2X158.2 171.4X064.5 TABLE SS. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for normal speakers in the noise-low predictability condition.

Subject sf mean\S.D. wf meariSS.D. nf meanXS.D. sent voicXS.D. wd voicXS.D. nuc voicXS

Norm 1 145.8X8.9 125.8N06.8 120.GN09.9 54.9X9.5 51.1X22.5 79.6X21.0 Norm 2 103.6X2.2 092.2X03.5 092.1X03.7 68.8X9.7 66.0X20.1 92.6X17.5 Norm 3 100.9X4.3 089.1X03.6 087.0N04.6 50.4X4.7 46.3X14.4 95.7X08.1 Norm 4 103.1X3.3 099.1X04.8 098.0N04.5 61.1X6.3 49.3X15.8 99.4X01.8 Norm 5 131.9X5.2 128.3X09.1 112.5X12.9 60.0X8.7 39.9X11.0 80.9X15.4 Norm 6 149.7X3.7 139.2N07.2 135.7X06.5 62.4X6.2 47.8X13.6 86.0X19.1 Norm 7 115.2X5.4 108.0M6.8 108.9X28.6 60.2X9.7 44.3X13.0 83.7X12.6 Norm 8 155.6X4.6 152.6X15.8 152.7X16.8 62.1X8.2 54.4X19.7 94.8X06.2 Norm 9 120.1\5.6 113.7X18.9 110.3X15.7 55.2X7.2 48.6X15.5 85.1X19.3 TABLE 56. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for normal speakers in the noise-high predictability condition.

Subject dB seniNS.D. dB wordXS.D. dB nucXS.D. sent duiXS.D. wd dui^.D. nuc dui\S.D.

Norm 1 78.7X1.5 74.1X2.7 77.3X3.4 1802.3X197.2 494.3X078.2 166.6X088.7 Norm 2 75.9M.6 74.9X1.8 77.7X1.6 2297.8X225.8 605.3X106.6 260.4X090.0 Norm 3 78.2M.2 74.2X2.3 77.6X2.5 2162.9X240.3 467.9X111.0 159.0X045.1 Norm 4 75.8\1.4 74.0X2.4 78.1X1.7 2366.7X310.6 513.4X098.6 183.7X103.8 Norm 5 75.2X0.7 72.1X1.8 75.0X3.4 2557.3X392.2 602.6X145.4 181.0X079.7 Norm 6 78.8X0.9 74.1X2.2 76.8X3.3 2211.8X230.8 508.3X084.9 217.6X069.6 Norm 7 77.4X1.7 75.0X1.3 77.7X1.9 1968.9X141.0 505.0X110.1 189.1N063.0 Norm 8 78.2X1.5 75.6X2.3 78.4X3.7 2014.4X232.6 540.7X078.0 205.4X056.7 Norm 9 77.7X1.7 74.0X2.5 76.8X2.8 1739.6X233.1 450.4X113.9 200.6^)86.3 TABLE 57. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for normal speakers in the noise-high predictability condition.

Subject sf meanXS.D. wf meanXS.D. nf meanXS.D. sent voicXS.D. wd voicXS.D. nuc voicXS

Norm 1 151.9X8.6 127.3X10.1 120.1X10.5 50.6X8.4 34.1X06.5 73.4X17.9 Norm 2 105.7X3.3 092.8X03.9 092.9X06.4 70.9X6.4 61.2X11.8 94.7X08.7 Norm 3 100.4X5.5 093.0X06.4 089.1X06.8 54.5X5.8 48.0X14.7 87.1X12.7 Norm 4 105.6X6.1 106.3X18.2 100.3X08.2 58.7X7.8 45.9X14.3 96.3 m 6 Norm 5 125.2X5.5 113.3X09.8 106.0X14.0 58.5X7.7 36.6X13.9 71.4X25.9 Norm 6 148.6X2.7 135.2X08.3 130.9X11.3 61.4X9.4 39.6X08.8 72.8X18.6 Norm 7 114.0X7.0 099.5X12.3 100.3X23.8 58.7X3.5 47.6X10.3 86.3X14.6 Norm 8 154.4X6.5 136.1X13.8 134.6X17.5 65.5X5.1 55.0X12.8 88.9X17.1 Norm 9 126.2X5.7 109.7X07.5 108.2X09.9 60.0X9.4 46.6X11.2 81.3X13.2 TABLE 58. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for hemilaryngectomy speakers in the no noise-low predictability condition.

Subject dB sentNS.D. dB wortfsS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D.

Hemi 1 69.6X1.2 65.8X2.5 68.2X2.7 1921.1X354.3 568.4X86.2 227.1X087.7 Hemi 2 75.0x1.1 72.5X2.5 74.4X2.9 1977.4X268.7 474.9X71.9 213.8X063.1 Hemi 3 68.7X1.8 64.7X2.2 67.0X2.7 2093.3X248.7 569.8X57.6 185.(N)73.8 Hemi 4 62.5X2.0 62.2X2.7 63.8X3.4 2516.6X228.4 671.6x75.1 257.8X093.4 Hemi 5 60.2\3.1 57.7X3.9 56.7X3.7 3281.2X521.3 542.3X86.1 250.4X134.6 Hemi 6 69.7X1.0 67.6X2.0 70.8X1.9 2013.2X277.8 608.3X54.0 202.6X072.7 Hemi 7 68.5X1.4 67.5X3.2 71.0X2.5 2721.3X424.4 566.2X86.5 lbbJ'OSS.S Hemi 8 64.7X1.4 63.2X2.8 63.1X2.4 2261.0X483.5 554.1X73.5 200.8X080.1 Hemi 9 82.6V1.1 77.1X2.3 80.7X2.9 2192.8X295.9 572.2X87.2 174.6X079.0 186 TABLE 59. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for hemilaryngectomy speakers in the no noise-low predictability condition.

Subject sf meanXS.D. wf meanXS.D. nf meanXS.D. sent voicXS.D. wd voicXS.D. nuc voicXS.D.

Hemi 1 188.3X09.2 179.5X29.1 182.7X29.8 57.8X06.7 43.5X18.0 74.7X26.1 Hemi 2 168.2X08.8 158.5X13.6 157.3X12.8 66.6X06.8 53.5X18.3 80.6X24.7 Hemi 3 173.CN05.6 164.4X05.6 162.5X10.1 71.3X07.7 53.7X20.1 93.8X09.7 Hemi 4 206.7X20.6 211.3X14.5 211.9X19.9 41.3X10.1 38.8X11.5 71.2X24.3 Hemi 5 168.0X29.2 118.2X77.3 095.1X73.0 31.8X04.5 20.2X17.2 26.0X24.7 Hemi 6 092.3X05.7 097.1X15.2 093.5X19.2 55.5X04.4 41.1X11.6 82.2X19.9 Hemi 7 086.7X04.3 075.5X04.6 075.4X04.9 52.7X11.2 46.4X17.5 93.7X06.9 Hemi 8 139.4X34.4 110.2X76.6 069.3X54.4 26.8X17.0 16.5X12.1 29.1X28.8 Hemi 9 177.1X06.3 156.9X12.9 154.9X13.8 61.8X06.0 41.8X19.5 89.9X19.4

oo ^ 4 TABLE 60. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for hemilaryngectomy speakers in the no noise-high predictability condition.

Subject dB sentXS.D. dB wordsS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D

Hemi 1 69.5X1.0 65.5X3.5 66.5X3.5 2111.2X596.2 578.7X081.1 222.7V) 1.0 Hemi 2 75.3X0.9 73.1X3.2 75.2X3.0 2030.8X162.8 514.6X070.0 230.4X48.3 Hemi 3 68.9X1.5 66.2X2.1 69.9X1.7 1972.6X191.5 578.4X061.2 159.1X56.8 Hemi 4 62.0X1.4 60.7X2.3 63.3X3.0 2709.6X280.7 669.4X094.9 220.2X48.4 Hemi 5 61.8X2.1 58.1X3.0 58.3X3.4 3256.7X733.5 588.6X121.1 249.3X73.2 Hemi 6 70.6X1.1 67.8X2.8 71.6X2.2 2056.7X259.8 550.0X122.0 170.8X57.7 Hemi 7 67.7X1.8 66.9X1.6 70.2X1.8 2883.9X557.0 551.3X092.8 170.7X45.3 Hemi 8 63.8X1.7 62.4X2.7 62.3X2.4 2125.5X208.7 570.4X074.8 206.2X48.1 Hemi 9 81.8X1.6 76.7X2.0 79.9X2.4 2044.1X316.7 608.CM02.6 198.2X84.6 TABLE 61. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for hemilaryngectomy speakers in the no noise-high predictability condition.

Subject sf meanXS.D. wf meanXS.D. nf mean\S.D. sent voicXS.D. wd voicXS.D. nuc voicXS.D.

Hemi 1 190.2X12.5 182.5X016.1 180.1X20.0 60.4X09.3 45.6X19.6 70.5X25.2 Hemi 2 163.1VJ8.2 155.1X019.0 154.5X19.9 70.9X07.8 57.6X19.0 83.4X17.8 Hemi 3 172.5N04.1 163.CN004.3 162.6X07.5 75.6X07.6 58.5X15.1 99.0X03.0 Hemi 4 205.5X27.6 199.9X050.6 198.2X51.6 34.9X08.7 33.6X12.2 78.5X18.2 Hemi 5 198.1X28.4 127.9X066.8 109.5X69.4 35.0X11.9 23.3X19.0 35.1X30.6 Hemi 6 089.5X04.9 093.2X015.1 099.1X29.5 64.9X11.0 42.7X18.2 88.5X10.6 Hemi 7 086.9X03.6 074.1X004.2 072.3X04.9 54.1X11.0 52.2X15.3 95.8X05.8 Hemi 8 147.8X30.3 149.8X123.8 078.3X97.5 23.5X15.0 14.3X16.7 26.4X39.0 Hemi 9 172.8X09.3 152.8X017.6 148.5X24.9 67.1X09.1 51.4X24.4 91.2X11.7 TABLE 62. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for hemilaryngectomy speakers in the noise-low predictability condition.

Subject dB sentXS.D. dB wordvS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D.

Hemi 1 70.3X1.7 65.2X2.0 67.7X2.4 1981.2X449.6 530.4X055.9 224.1X050.8 Hemi 2 80.0x1.0 77.0X1.8 80.1X2.1 2118.7X303.7 523.1X098.2 179.1X073.9 Hemi 3 72.0X0.7 69.3X1.2 72.4X2.2 2011.6X213.2 558.4X108.9 199.0X048.4 Hemi 4 62.6X2.4 61.0X3.9 63.2X3.6 2681.8X302.9 748.7X181.8 255.7X103.1 Hemi S 61.6X1.6 58.5X3.8 57.7X5.6 3563.4X757.3 606.6X092.1 249.1X058.6 Hemi 6 73.9X0.9 73.8X2.5 75.7X2.3 1942.1X241.3 498.1X130.9 211.6X114.4 Hemi 7 76.6X1.5 76.0X1.1 79.5X1.5 2646.7U79.5 639.4X031.4 221.4X075.7 Hemi 8 74.3X1.2 74.3X3.3 74.3X2.7 2170.3X539.9 578.5X049.0 187.1X033.6 Hemi 9 83.8X1.4 81.0X3.1 83.8X4.0 1933.9X271.3 564.5X109.9 218.0X070.1 0 9 1 TABLE 63. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for hemilaryngectomy speakers in the noise-low predictability condition.

Subject sf meanNS.D. wf meanNS.D. nf mean\5.D. sent voicNS.D. wd voicNS.D. nuc voicNS.D.

Hemi 1 187.2X15.4 172.1X39.1 172.5X039.8 62.0x06.2 42.3X10.5 73.5X23.4 Hemi 2 173.1N04.9 160.3X21.4 155.3X020.1 63.6X06.4 51.0X10.1 95.4X10.1 Hemi 3 186.8X03.2 180.7N07.5 184.8X008.6 70.CM0.1 56.3X17.4 97.1X05.6 Hemi 4 131.2X35.0 118.9N36.0 111.8X029.8 48.1X08.9 39.7X14.8 76.6X25.5 Hemi 5 167.2X37.2 112.5X65.8 085.6X076.6 34.3X07.0 22.4X14.8 29.9X32.9 Hemi 6 096.1X05.9 090.9X08.4 091.2X008.9 65.0X11.7 57.6X18.7 81.1X17.8 Hemi 7 108.5X04.3 098.6X09.1 101.2X007.5 59.2X11.6 53.8X17.4 96.0X08.7 Hemi 8 144.3X32.9 145.0X54.4 161.8X115.7 37.1X13.2 32.6X18.2 55.9X39.5 Hemi 9 177.9X06.2 163.8N09.5 163.9X008.1 64.5X10.1 63.1X18.7 94.9X16.2 TABLE 64. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for hemilaryngectomy speakers in the noise-high predictability condition.

Subject dB sentXS.D. dB wordxS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D.

Hemi 1 72.5X1.9 66.4X1.4 68.6X1.9 2101.0447.4 556.0X079.4 249.1X103.4 Hemi 2 80.0X1.0 77.0X2.9 79.4X3.1 2249.1X222.0 541.8X055.5 209.2X083.6 Hemi 3 72.7X1.6 70.2X1.7 71.6X2.9 2106.7X157.0 579.6X050.7 252.6X093.1 Hemi 4 62.8X2.4 61.0X2.9 63.8X3.0 2846.7X565.3 714.5X106.5 231.5X059.7 Hemi 5 62.0X1.7 58.3X3.4 58.2X2.2 3777.9X609.7 614.7X091.9 256.3X112.9 Hemi 6 73.0X0.9 71.2X1.7 73.7X1.6 2094.2X180.0 545.9X116.4 246.7X083.6 Hemi 7 77.4X0.9 75.0X1.7 77.1X2.1 2643.1M20.4 652.9X112.9 275.7X132.8 Hemi 8 74.2X1.2 72.7X2.4 72.6X2.3 2162.2X174.3 576.8X029.0 230.8X094.9 Hemi 9 83.2X1.3 80.1X2.2 83.4X2.2 2218.0x321.4 605.3X058.9 205.9X062.6 TABLE 65. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for hemilaryngectomy speakers in the noise-high predictability condition.

Subject sf meanXS.D. wf meanXS.D. nf meanXS.D. sent voicXS.D. wd voicXS.D. nuc voicXS.D.

Hemi 1 196.5X14.4 187.5X28.9 185.7X032.1 60.1X06.3 40.2X09.1 72.1X18.7 Hemi 2 173.009.5 161.6X13.2 161.3X014.2 67.2X13.4 58.9X17.5 88.4X21.2 Hemi 3 186.8X03.2 177.7X05.7 177.4N009.1 73.2X07.9 62.7X15.3 91.4X11.8 Hemi 4 130.3X32.5 155.1X93.5 162.5X100.4 53.2X11.6 40.6X11.3 84.5X08.1 Hemi 5 182.8X28.6 124.8X17.7 118.6X026.2 37.8X06.6 24.7X13.0 34.0X17.1 Hemi 6 094.7X05.4 094.9X12.2 095.9X015.9 66.4X06.9 50.0X17.2 77.2X17.2 Hemi 7 106.5X05.2 095.7X07.6 094.0007.2 63.5X10.7 56.7X14.3 93.1X12.0 Hemi 8 151.8X23.0 132.4X73.6 128.1VD78.6 39.8X10.7 29.2X18.1 45.9X28.7 Hemi 9 178.2X05.6 161.2X10.1 160.6X010.7 64.0X10.9 52.8X20.3 94.3X11.1 TABLE 66 Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for supraglottic laryngectomy speakers in the no noise-low predictability condition.

Subject dB sentXS.D. dB wordXS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.E

Supra 1 80.5X1.7 75.7X2.2 78.9X2.3 1947.5X337.8 421.9X037.1 149.7X66.0 Supra 2 75.5X1.2 71.9X3.1 74.9X2.6 2927.7X468.4 621.6X116.5 199.5X80.9 Supra 3 72.3X2.2 70.2X2.1 74.4X3.0 2625.6X468.0 538.8X141.8 176.1X42.8 Supra 4 71.0X3.0 65.2X2.6 67.9X2.9 2383.6X384.6 589.9X104.5 152.7X56.3 Supra S 72.4X1.3 69.4X2.6 73.8X2.3 2158.4X291.3 590.6X090.8 163.9X57.4 Supra 6 67.3X0.9 62.0X1.5 65.7X1.8 2207.7X391.7 580.6X107.9 166.6X44.8 Supra 7 73.4X1.5 71.3X2.5 74.5X2.2 2664.2X362.6 702.9X070.0 247.9X83.4 Supra 8 69.6X2.2 64.0X1.6 67.0X1.6 2144.9X434.1 452.9X067.8 168.6X75.7 Supra 9 70.1X1.9 63.8X2.2 66.0X2.8 1995.9X350.6 510.8X061.3 173.4X66.6 4 9 1 TABLE 67. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for supraglottic laryngectomy speakers in the no noise-low predictability condition.

Subject sf meanNS.D. wfmeanNS.D. nfmeanXS.D. sentvoicXS.D. wd voicXS.D. nucvoicXS.

Supra 1 090.6X04.2 082.4X005.5 080.1X005.5 55.2X08.5 41.8X12.9 74.4X19.0 Supra 2 113.0N03.8 101.4X006.3 097.9N006.5 58.9X03.3 45.3X12.7 93.3X07.4 Supra 3 106.6X22.4 144.9X112.0 151.7X118.8 45.5X08.5 36.5X14.0 81.6X11.6 Supra 4 124.4N13.3 115.4X058.7 132.4X083.1 46.4X08.0 26.3X18.0 54.4X30.9 Supra S 112.4X05.2 106.CN014.7 100.4X016.1 56.3X06.5 39.8X11.5 88.8X12.5 Supra 6 086.9X02.4 081.2X005.2 076.9X003.8 53.9X09.0 36.4X11.3 78.5X11.3 Supra 7 148.8X06.4 144.6X011.0 142.8X010.2 57.3X06.6 41.3X15.1 86.5X14.6 Supra 8 094.5X04.8 080.5X006.4 079.9ND10.2 44.CM0.4 38.2X12.8 80.4X15.9 Supra 9 101.8X02.4 091.8X006.1 086.8X005.6 54.1X07.1 32.3X07.4 63.5X19.4 TABLE 68. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for supraglottic laryngectomy speakers in the no noise-high predictability condition.

Subject dB sentXS.D. dB wordXS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D.

Supra 1 80.6x1.7 75.1X3.3 77.5X3.5 2018.7X397.4 379.2X069.6 143.1X026.2 Supra 2 75.2X0.7 71.5X3.7 73.6U.2 2894.9X509.7 541.5X169.8 204.4X081.4 Supra 3 72.1X2.1 67.7X3.1 71.5X3.9 2542.6X326.0 542.7X110.3 196.9X100.4 Supra 4 68.6X2.6 62.5X2.1 65.9X2.8 2340.3X272.5 510.1X067.4 146.3X055.2 Supra S 72.6X1.8 69.7X1.9 71.7X3.6 2364.9N429.1 575.4X097.8 171.1X047.4 Supra 6 68.0M.6 64.1X2.3 67.5X2.4 2299.6X224.1 582.6X089.4 196.1X093.2 Supra 7 72.8X0.5 70.3X2.4 73.8X1.3 2802.1X282.6 669.CM07.1 244.9X085.4 Supra 8 69.4X1.6 61.6X2.0 64.9X1.9 2256.1X314.4 502.6X089.9 171.8X045.9 Supra 9 69.3X1.2 62.7X2.6 64.4X3.1 1880.9X220.5 485.2X088.3 177.4X049.6 TABLE 69. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for supraglottic laryngectomy speakers in the no noise-high predictability condition.

Subject sf meanXS.D. wfmeanXS.D. nfmeanXS.D. sentvoicXS.D. wd voicXS.D. nucvoicXS.

Supra 1 089.8X03.7 078.4X006.2 075.0007.7 53.1X11.6 39.9X14.3 65.1X21.0 Supra 2 109.804.3 098.3X006.4 096.8011.3 63.9X11.7 59.3X22.4 90.2X15.2 Supra 3 108.1X22.7 146.8X144.7 143.5X136.9 48.4X14.1 29.4X14.3 67.2X22.6 Supra 4 121.5X11.1 124.2X064.2 110.5078.0 48.508.5 20.4X12.6 43.5X29.6 Supra S 116.7X08.9 122.3S031.2 136.6082.8 65.3X13.6 47.5X13.3 86.4X15.4 Supra 6 087.1\02.1 079.7X003.6 078.7X004.3 64.5X10.0 46.0X18.9 90.2X13.9 Supra 7 148.5X03.3 140.0005.3 140.1006.5 61.8X09.9 45.4X22.5 92.0X11.3 Supra 8 095.105.3 079.7X005.3 076.9X006.9 50.3X15.3 33.2Y20.2 65.6X22.1 Supra 9 100.2\02.8 088.2X004.5 085.2004.6 60.8X09.5 39.0X18.1 63.7X27.7 TABLE 70. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for supraglottic laryngectomy speakers in the noise-low predictability condition.

Subject dB seniXS.D. dB wordxS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D.

Supra 1 85.7X1.4 82.4X2.1 84.6X1.9 2081.8X589.9 454.9X119.5 183.8X081.2 Supra 2 77.3X1.0 74.2X2.2 76.9X3.0 2667.6X641.5 549.3X107.4 198.8X105.0 Supra 3 78.2X2.1 75.5X2.7 77.8X3.4 2653.4X495.1 601.1X097.8 223.3X108.2 Supra 4 73.9X1.7 67.1X1.9 69.3X2.8 2469.9X208.3 611.6X121.9 217.6X100.4 Supra 5 73.2X1.8 70.6X2.6 74.6X3.1 2250.4X394.7 668.CM53.7 190.7X049.3 Supra 6 73.4X1.3 69.9X1.6 73.2X1.7 2613.1X561.1 612.6X097.0 200.2X079.5 Supra 7 78.3X1.5 77.5X2.7 80.2X3.0 2775.9X375.8 770.0X107.0 286.9X069.1 Supra 8 74.CM.2 70.1X2.7 72.3X2.4 2161.4X343.2 457.7X081.2 200.0N070.2 Supra 9 74.9X1.1 71.1X2.1 73.8X2.7 2246.4M53.9 544.9X100.7 173.4X044.0 TABLE 71. Descriptive statistics (MeanXStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf)> key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for supraglottic laryngectomy speakers in the noise-low predictability condition.

Subject sf meanNS.D. wfmeanNS.D. nfmeanXS.D. sentvoicXS.D. wd voicXS.D. nucvoicXS,

Supra 1 104.2N05.4 097.0N14.7 093.3X023.5 56.5X10.8 47.8X10.5 83.4M)8.2 Supra 2 112.1N04.5 100.0X08.1 101.1X010.6 63.1X08.6 65.9X15.7 95.5X07.5 Supra 3 111.1X23.8 132.9X87.2 150.7X121.3 53.1X06.9 45.2X12.7 75.5X18.5 Supra 4 111.2X08.5 121.0X43.9 116.9X074.4 48.3X09.8 29.8X15.6 54.4X30.7 Supra S 121.3^)5.3 113.3X16.0 112.1X020.6 61.1X07.2 47.0X14.2 98.1X03.2 Supra 6 109.4m 1 101.8X12.3 105.4X016.2 63.4X11.0 49.7X15.4 91.8X10.2 Supra 7 160.2M5.6 156.6X33.0 164.4X043.5 69.6X08.5 59.3X16.7 93.7X09.0 Supra 8 104.6X03.5 087.5X05.1 084.7X007.2 55.8X08.3 49.1X15.2 78.0X17.4 Supra 9 108.5^)2.1 099.9X04.1 097.4X005.9 63.CM 0.4 47.8X08.6 90.6X12.9 TABLE 72. Descriptive statistics (MeanNStandard Deviation) from the acoustical measures of intensity (in dB SPL) of the sentence (dB sent), key word (dB word), & vowel nucleus (dB nuc), and of duration (in ms) of the sentence, (sent dur) key word (wd dur), & vowel nucleus (nuc dur) for supraglottic laryngectomy speakers in the noise-high predictability condition.

Subject dB senf\S.D. dB wordXS.D. dB nucXS.D. sent duiXS.D. wd duiXS.D. nuc duiXS.D.

Supra 1 85.1X1.4 83.0X2.1 85.8X1.7 2090.2X235.7 473.6X044.5 233.5X072.1 Supra 2 76.9X1.2 72.3X2.3 75.5X3.1 2456.3X144.9 610.0X102.7 249.6X127.9 Supra 3 77.3X1.3 75.6X2.4 79.9X2.1 2761.CM29.0 665.9X149.8 217.9X059.7 Supra 4 73.8M.7 67.0X2.8 67.2X3.2 2465.5X330.3 586.8X106.6 229.4X115.4 Supra 5 74.2X1.6 71.8X1.5 75.2X1.4 2301.8X324.8 634.7X132.6 231.5X065.6 Supra 6 74.CM.0 71.5X2.2 74.0X2.4 2494.8X217.4 645.9X075.2 265.0N073.7 Supra 7 78.4\1.1 76.4X1.6 79.3X2.8 3020.7X221.4 755.2X057.5 294.2X141.2 Supra 8 73.4X1.4 68.0X2.2 72.1X3.0 2275.8X387.1 538.9X084.9 191.2X072.8 Supra 9 75.4X1.2 70.3X1.7 73.5X2.3 1979.8X255.4 488.0X086.2 177.6s050.8 200 TABLE 73. Descriptive statistics (MeanNStandard Deviation) from the acoustical measures of fundamental frequency (Hz) of the sentence (sf), key word (wf), & vowel nucleus (nf), and of percentage of voicing of the sentence (sent voice), key word (wd voice), & vowel nucleus (nuc voice) for supraglottic laryngectomy speakers in the noise-high predictability condition.

Subject sf meanNS.D. wfmeanNS.D. nfmeanNS.D. sentvoic\S.D. wd voicNS.D. nucvoicNS.

Supra 1 102.7N02.9 091.8N05.9 089.3V)5.8 62.2N04.6 52.0N12.5 86.709.2 Supra 2 114.5N04.5 101.3N04.0 101.4N06.3 70.006.8 51.0N13.1 95.009.3 Supra 3 104.4N12.4 141.4N36.7 129.2N43.7 51.&10.6 43.8N19.1 86.9N12.3 Supra 4 U0.0N05.3 090.8N30.0 089.8N37.6 51.2N11.0 38.9N16.3 66.3N24.7 Supra S 119.904.6 096.8N12.5 097.4N14.2 66.2N08.4 53.2N20.6 96.2N05.1 Supra 6 106.9S02.9 099.1N04.1 098.7N04.3 68.5N06.0 58.6N14.9 92.6N12.5 Supra 7 155.3N13.7 137.4N37.0 131.2N33.9 64.7N07.9 50.4NI1.5 89.5N19.0 Supra 8 105.5^03.7 086.3N08.9 084.7N08.4 52.6N07.0 36.709.9 83.2N14.5 Supra 9 108.4N03.7 098.8\07.8 096.2\05.9 64.009.2 49.7N14.8 93.5N10.6 APPENDIX G

MEDICAL INFORMATION OF POST SURGERY SPEAKERS

202 203

Table 74. Medical information on supraglottic laryngectomy speakers.

SUPRAGLOTTIC LARYNGECTOMY SPEAKERS

SUBJECTRADIATION SURGICAL INVOLVEMENT-TAKEN TREATMENTS FROM PATIENT'S MEDICAL FOLLOWING CHARTS SURGERY

NO Suprahyoid epiglottis, cricophaiyngeal myotomy

2 NO Supraglottic laryngectomy

3 NO Supraglottic laryngectomy, partial pharyngectomy, & L radical neck dissection

4 NO L Suprahyoid epiglottis, aryepiglottic fold

5 NO Supraglottic laryngectomy

6 YES L Supraglottic epiglottis, aryepiglottic fold, partial pharyngectomy, partial glossectomy, L radical neck dissection, pectoralis major muscle flap

7 NO L Supraglottic laryngectomy

8 YES Supraglottic laryngectomy, R neck dissection, cricopharyngeal myotomy

YES Supraglottic laryngectomy, R radical neck dissection, tongue base resection with pectoralis myocutaneous flap reconstruction, cricopharyngeal myotomy 204

Table 75. Medical information on hemilaryngectomy speakers.

HEMILARYNGECTOMY SPEAKERS

SUBJECT RADIATION SURGICAL INVOLVEMENT-TAKEN TREATMENTS FROM PATIENTS MEDICAL FOLLOWING CHARTS SURGERY

1 NO L ffontolateral, L true vocal fold, L anterior commissure, L arytenoid

2 NO L true vocal fold

3 NO Frontal hemilaryngectomy, portions of L & R true vocal fold and anterior commissure

4 NO L true vocal fold

5 NO R true vocal fold, post surgery injection of teflon in anterior right fold where resection occured

6 NO R true vocal fold

7 NO R true vocal fold

8 YES L true vocal fold

9 YES L true vocal fold APPENDIX H

EXAMPLE OF MARKED SENTENCE USING WAVES +

205 206

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EXAMPLE OF MARKED VOWEL NUCLEUS USING WAVES +

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