CONTROL OF LEXICAL INHIBITION IN ASL AND ENGLISH-READING SENTENCE COMPREHENSION IN DEAF AND HEARING ASL USERS by Emily Goldberg Bachelor of Philosophy, University of Pittsburgh, 2015 Submitted to the Graduate Faculty of School of Health and Rehabilitation Sciences in partial fulfillment of the requirements for the degree of Master of Science University of Pittsburgh 2017 UNIVERSITY OF PITTSBURGH SCHOOL OF HEALTH AND REHABILITATION SCIENCES This thesis was presented by Emily Goldberg It was defended on April 26, 2017 and approved by Malcolm McNeil, PhD, Communication Sciences and Disorders, University of Pittsburgh Michael Dickey, PhD, Communication Sciences and Disorders, University of Pittsburgh Claude Mauk, PhD, Less Commonly Taught Languages Center, University of Pittsburgh Thesis Advisor: Sheila Pratt, PhD, Communication Sciences and Disorders ii Copyright © by Emily Goldberg 2017 iii CONTROL OF LEXICAL INHIBITION IN ASL AND ENGLISH-READING SENTENCE COMPREHENSION IN DEAF AND HEARING ASL USERS Emily Goldberg, M.S. University of Pittsburgh, 2017 Background: Language experiences of Deaf individuals are variable and impact cognitive- linguistic functioning. Deaf individuals in the U.S. who use American Sign Language (ASL) as their primary communication method must learn to read and write in English; however they typically exhibit difficulty in doing so due to many factors. Cognitive-linguistic functions, such as inhibition and other executive attentional mechanisms, play a key role in literacy acquisition. One task that measures inhibitory functions is the Stroop task. The Stroop effect has been studied in the Deaf ASL population, however results were inconclusive and studies have focused on the single-word level only. Procedures: This study included 15 hearing non-proficient (HNP), 15 hearing proficient (HP), and 15 Deaf proficient (DP) ASL users. The participants completed an ASL single-word Stroop task, the ASL and English Reading Word Fade versions of the sentence-length Computerized Revised Token Test (CRTT), and the ASL and English Reading Word Fade Stroop versions of the CRTT. Results: No groups demonstrated a reliable Stroop effect for the single-word ASL task, but 10 participants from the DP group did show a Stroop effect on this task. The DP group was the only group to demonstrate a color word Stroop effect on the CRTT ASL Reading Word Fade Stroop ii task. All groups demonstrated a significant Stroop effect for the English Reading Word Fade Stroop task. The DP group demonstrated larger interference in English than the hearing groups, and produced lower Mean-CRTT scores across both languages. Language proficiency did not predict a Stroop effect for any group for either language, however, individuals that were more language proficient were faster to respond to the sentence-level stimuli than the less proficient. Conclusions: The DP group demonstrated lexical processing in both ASL and English at the sentence level, evidenced by observable Stroop effects, however the magnitude of the effects suggest reduced inhibitory control or slow lexical activation observed in the bilingual (ASL- English) population. At the single-word level, individual participant factors influenced the presence of a Stroop effect. The DP group was slower to read words in all tasks across both languages, suggesting requirement for additional processing time. iii TABLE OF CONTENTS PREFACE ...................................................................................................................................... ii 1.0 INTRODUCTION............................................................................................................. 1 2.0 BACKGROUND ............................................................................................................... 1 2.1 AMERICAN SIGN LANGUAGE: A BRIEF OVERVIEW ...................................... 1 2.1.1 Language Learning Experiences ............................................................................. 2 2.2 DEAF BILINGUALISM................................................................................................ 4 2.3 DEAF LITERACY SKILLS ......................................................................................... 6 2.3.1 Reading Instruction .................................................................................................. 7 2.3.2 Working Memory...................................................................................................... 8 2.4 THE COMPUTERIZED-REVISED TOKEN TEST ............................................... 12 2.5 THE STROOP EFFECT ............................................................................................. 15 2.5.1 Developmental Effects ............................................................................................ 18 2.6 THE BILINGUAL ADVANTAGE ............................................................................. 19 2.7 STROOP EFFECT IN DEAF SIGNERS ................................................................... 23 2.8 EXPERIMENTAL QUESTIONS AND HYPOTHESES ......................................... 26 3.0 METHODS ...................................................................................................................... 28 3.1 PARTICIPANTS .......................................................................................................... 28 3.1.1 Inclusion Criteria and Preliminary Procedures................................................... 30 ii 3.2 STIMULI....................................................................................................................... 35 3.3 PROCEDURES ............................................................................................................ 39 3.3.1 Location of Testing and Devices ............................................................................ 39 3.3.2 Single-word ASL Stroop Task ............................................................................... 40 3.3.3 Sentence Level Stroop Tasks.................................................................................. 41 3.4 ANALYSIS .................................................................................................................... 42 4.0 RESULTS ........................................................................................................................ 44 4.1 ASL SINGLE-WORD STROOP ................................................................................ 44 4.2 CRTT-ASL STROOP .................................................................................................. 48 4.3 CRTT-R-WF-STROOP ....................................................................................................... 55 4.4 RELATIONSHIP BETWEEN PROFICIENCY AND STROOP EFFECT ........... 61 5.0 DISCUSSION .................................................................................................................. 68 5.1 THE ASL SINGLE-WORD STROOP TASK ........................................................... 69 5.2 CRTT-R-WF AND CRTT-R-STROOP ENGLISH SENTENCE-LEVEL PERFORMANCE ................................................................................................................... 76 5.3 CRTT-ASL AND CRTT-ASL-STROOP SENTENCE-LEVEL PERFORMANCE .. 78 5.4 LANGUAGE PROFICIENCY AND THE STROOP EFFECT .............................. 81 5.5 IMPLICATIONS OF FINDINGS .............................................................................. 84 6.0 FUTURE CONSIDERATIONS ..................................................................................... 87 APPENDIX .................................................................................................................................. 90 BIBLIOGRAPHY ..................................................................................................................... 104 iii LIST OF TABLES Table 1. CRTT scoring system. ................................................................................................... 14 Table 2. Age and sex of participants. .......................................................................................... 30 Table 3. Mean score and standard deviation on reading subtest of the CELF-5......................... 31 Table 4. Background questionnaire items. .................................................................................. 32 Table 5. Median and range self-rating of proficiency of English and ASL on the LEAP-Q. ..... 33 Table 6. Mean, median, and range of years of formal education ................................................ 33 Table 7. SLPI level to value translation. ..................................................................................... 35 Table 8. Self-rated SLPI median and range scores. .................................................................... 35 Table 9. Mean reading times, time differences, and efficiency scores for each group on control and incongruent conditions for the single-word ASL Stroop task. ............................................... 45 Table 10. Regression estimates, standard errors, and t-values for main effects of condition and group on color word, and interaction for the single-word ASL Stroop task................................. 46 Table 11. Regression estimates, standard errors, and t-values for main effects of condition and group on Average Mean ASL single-word Score, and interaction for the single-word ASL Stroop task. ..............................................................................................................................................