Poster F44, Tuesday, March 27, 8:00-10:00 am, Exhibit Hall C
Linking Auditory Processing and Lexical Representation via Phonological Discrimination
Vivi Tecoulesco1, Erika Skoe1, Letitia Naigles1; 1University of Connecticut
Auditory Brainstem Responses (ABRs) are auditory evoked potentials recorded on the scalp that reveal the earliest stages of auditory processing. Unstable neural responses to speech sounds may be characteristic of reading-impaired populations; moreover, other language-impaired populations may likewise have unstable neural responses to sound. Thus, stability of auditory processing may support language development in both typical and atypical populations. This project studies the connections between auditory processing and language learning using a phonological discrimination task, which by hypothesis links early auditory processing and macro-level language competency. Eight typically-developing children (TD) and eight diagnosed with autism spectrum disorder (ASD) participated; MAs = 11 years in each group. All were screened for normal hearing thresholds before ABRs were recorded in response to a “da” stimulus (10.9/sec, 6000 trials). Phonological discrimination was assessed in a same/different task utilizing pairs of novel, bisyllabic, consonant-vowel-consonant words. Current language ability was measured using the CELF-5. The TD group performed significantly more accurately on phonological discrimination and on the CELF-5 than the ASD group. Neural response consistency was positively correlated with phonological discrimination ability in the ASD but not in the TD group. Bivariate correlations including both groups found that children with better phonological discrimination also had better language ability. Phonological discrimination appears to mediate the relationship between neural response consistency to speech sounds and current language ability (z'= 2.8, p =0.005). As group differences were not observed between TD and ASD groups, similar processes may be at work in both typical and atypical populations.
Topic Area: LANGUAGE: Lexicon