PSYCHOACOUSTICS Perception of Normal and Impaired Hearing with Audiology Applications Editor-in-Chief for Audiology Brad A. Stach, PhD PSYCHOACOUSTICS Perception of Normal and Impaired Hearing with Audiology Applications Jennifer J. Lentz, PhD 5521 Ruffin Road San Diego, CA 92123 e-mail: [email protected] Website: http://www.pluralpublishing.com Copyright © 2020 by Plural Publishing, Inc. Typeset in 11/13 Adobe Garamond by Flanagan’s Publishing Services, Inc. Printed in the United States of America by McNaughton & Gunn, Inc. All rights, including that of translation, reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, recording, or otherwise, including photocopying, recording, taping, Web distribution, or information storage and retrieval systems without the prior written consent of the publisher. For permission to use material from this text, contact us by Telephone: (866) 758-7251 Fax: (888) 758-7255 e-mail: [email protected] Every attempt has been made to contact the copyright holders for material originally printed in another source. If any have been inadvertently overlooked, the publishers will gladly make the necessary arrangements at the first opportunity. Library of Congress Cataloging-in-Publication Data Names: Lentz, Jennifer J., author. Title: Psychoacoustics : perception of normal and impaired hearing with audiology applications / Jennifer J. Lentz. Description: San Diego, CA : Plural Publishing, [2020] | Includes bibliographical references and index. Identifiers: LCCN 2018028617| ISBN 9781597569897 (alk. paper) | ISBN 1597569895 (alk. paper) Subjects: | MESH: Auditory Perception — physiology | Psychoacoustics | Hearing Loss, Sensorineural Classification: LCC QP461 | NLM WV 272 | DDC 612.8/5 — dc23 LC record available at https://lccn.loc.gov/2018028617 Contents Introduction ix Acknowledgments xii Reviewers xiii 1 History 1 Learning Objectives 1 Introduction 1 Early Investigation of Perception 1 The Origins of Psychoacoustics 3 The Advent of the Telephone 5 Auditory Assessment 7 References 11 2 Estimating Threshold in Quiet 13 Learning Objectives 13 Introduction 13 Acoustics: Pure Tones and the Decibel 14 Physiological Representation of Sound 20 Threshold of Human Hearing: MAP and MAF 25 Measuring the Threshold 31 Signal Detection Theory (SDT) 38 Summary and Take-Home Points 41 Exercises 41 References 43 3 Estimating Thresholds in Noise (Masking) 45 Learning Objectives 45 Introduction 45 Acoustics: Noise and Filters 46 Physiological Factors 50 Introduction to Masking 52 The Critical Band and the Auditory Filter 56 The Excitation Pattern 61 Psychophysical Tuning Curves and Suppression 65 Masking by Fluctuating Sounds 67 Masking and Sensorineural Hearing Loss 69 Clinical Implications of Masking 72 Summary and Take-Home Points 74 Exercises 75 References 76 v vi Psychoacoustics: Perception of Normal and Impaired Hearing with Audiology Applications 4 Loudness and the Perception of Intensity 79 Learning Objectives 79 Introduction 79 Acoustics: Intensity and the Decibel 80 Physiological Representation of Stimulus Level 81 Introduction to Measuring Loudness 83 Loudness and Intensity 84 Loudness and Frequency 88 Calculating Loudness 92 Reaction Time as a Measure of Loudness 93 Intensity Discrimination 96 Effects of Sensorineural Hearing Loss on Loudness 101 Summary and Take-Home Points 105 Exercises 105 References 107 5 Temporal Processing 109 Learning Objectives 109 Introduction 109 Temporal Resolution: Gap Detection 111 Temporal Resolution: Amplitude Modulation Detection 120 Temporal Masking 124 Comparison of Temporal Processing Measures 126 Temporal Integration 127 Effects of Hearing Loss on Temporal Processing 131 Summary and Take-Home Points 138 Exercises 138 References 140 6 Pitch Perception 141 Learning Objectives 141 Introduction 141 Acoustics: Harmonic Complex Tones 142 Theories of Pitch Perception 145 Pitch of Pure Tones: Subjective Measures 152 Pitch of Pure Tones: Frequency Discrimination 156 Mechanisms for Coding the Pitch of Pure Tones 158 Pitch of Complex Sounds 160 Importance of Pitch Perception in Everyday Listening 165 Pitch Perception in Listeners with SNHL 167 Summary and Take-Home Points 169 Exercises 169 References 171 Contents vii 7 Hearing with Two Ears 173 Learning Objectives 173 Introduction 173 Binaural Advantages to Detection and Discrimination 174 Localization in the Horizontal Plane: Acoustics 175 Sound Localization in the Horizontal Plane: Physiological Basis 180 Sound Localization in the Horizontal Plane: Perception 182 Sound Localization in the Median Plane 185 Lateralization 185 Binaural Unmasking 190 Impact of Hearing Loss on Binaural Hearing 196 Summary and Take-Home Points 199 Exercises 200 References 201 8 Clinical Implications 203 Learning Objectives 203 Introduction 203 Consequences of Impaired Perception 204 Effects of Amplification Strategies on Perception 207 Influence of Psychoacoustics on Diagnostic Audiology 212 Summary and Take-Home Points 218 Exercises 218 References 219 Glossary 221 Index 227 Introduction NOTES ON THIS TEXT presumed cochlear origin, and the term senso- rineural hearing loss will be used throughout I am writing this textbook after teaching psy- the text as such. chological acoustics (commonly referred to as The primary target audience is graduate psychoacoustics) to clinical audiology students students in audiology, who intend a clinical for over 15 years. Each year I have taught this career and need an understanding of both course I have struggled to find a text appro- normal and impaired auditory perception. priate for these students. No doubt, there are Because the field of psychoacoustics has pro- excellent texts available on the topic of psycho- foundly influenced clinical audiology, this acoustics. However, all modern books on the book also discusses history of the two fields and topic cover only normal auditory perception clinical implications and applications of psy- and contain little to no review of perception choacoustics. Students studying experimental by listeners with hearing loss. Yet, I argue that psychology, audio engineering, engineering, these students, and those studying auditory and hearing science may also find that this perception more generally, should have some book suits their needs. Notably, this text does exposure to the perceptual deficits imposed not assume that students have a strong back- by sensorineural hearing loss. Not only will ground in either acoustics or auditory physiol- having this information help clinical audi- ogy. However, because understanding both of ologists to better care for their patients, but these fields is important to fully understand studies evaluating perception in listeners with psychoacoustics and the physiological mecha- sensorineural hearing loss also have contrib- nisms responsible for the perception of sound, uted to our understanding of the mechanisms this text provides an overview of the necessary responsible for normal auditory perception. elements of acoustics and physiology, on an Consequently, this textbook provides a broad “as-needed” basis. overview of auditory perception in normal- The structure of the textbook differs hearing listeners, and each chapter includes from the other texts available on this topic. information on the effects that sensorineural Traditionally, texts generally present a chapter hearing loss has on perceptual abilities. on acoustics, one on auditory anatomy and When possible, this book will provide physiology, and sometimes a chapter on meth- mechanistic explanations for the psycho- odology before delving into chapters on indi- acoustical findings in terms of physiology. vidual topics within the realm of psychoacous- We will ask “why?” and “how?” with a goal tics. In contrast, this text takes an approach toward understanding what the auditory sys- similar to a problem-based approach in that tem is able to perceive and how the auditory each chapter presents self-contained infor- system achieves perception. The main focus of mation related to the acoustics, physiology, this text is healthy auditory perception. How- and methodologies as they apply to the spe- ever, as we work toward this goal, we will also cific topic being discussed. Naturally, certain evaluate the perceptual abilities of people with chapters may refer back to previous chapters sensorineural hearing loss. The focus here is for a review of certain information, but the on listeners with sensorineural hearing loss of degree to which this occurs is fairly limited. ix x Psychoacoustics: Perception of Normal and Impaired Hearing with Audiology Applications For the most part, each self-contained chapter topics. At the end of each chapter, there is a presents the necessary information for under- set of exercises designed to develop critical standing the specific topic. Essentially each thinking about psychoacoustics and to assist chapter includes the following topics: students in learning to apply psychoacoustic information to the more general fields of audi- • Introduction to the topic and its importance ology and auditory perception. Together, these • Relevant acoustics materials should allow students to develop a • Important physiological studies deeper understanding of psychoacoustic top- • Perception by normal-hearing listeners ics and how those topics relate to hearing loss • Perception by listeners who have sensori- and audiological practice. neural hearing loss Finally,