The relationship between auditory brainstem responses, cognitive ability, and speech-in-noise perception among young adults with normal hearing thresholds

The goal of this research was to determine the contributions of auditory neural processing and cognitive abilities to predict performance on a speech-in-noise perception task in young, normal hearing adults. Two experiments were performed, each with separate cohorts of ∼30 young adults with normal hearing who performed a competing talker task which included a high-pass filtered condition that was designed to be more sensitive to auditory nerve functioning than are commonly used speech-in-noise perception tests. Predictors of performance on this competing talker task included ABR waves I and V metrics and cognitive test scores. Experiment one included click ABRs at a moderate level commensurate with the level of the competing talker task, as well as the cognitive digit span working memory test. Experiment two included high-intensity click clinical ABRs and three cognitive tests from the NIH Toolbox V3 that assessed working memory, cognitive flexibility and attention, and inhibitory control: List Sorting Working Memory, Dimensional Change Card Sort, and Flanker Inhibitory Control and Attention tests, respectively. Performance on the high-pass filtered competing talker task varied across participants in both experiments. This variability was predicted by performance on the test of inhibitory control, but not the tests involving working memory or cognitive flexibility, nor by any of the auditory processing metrics from moderate or high-intensity click ABRs. Among two groups of young adults with normal hearing, cognitive factors with very similar demands to the competing talker task seem to play the greatest role in speech-in-noise perception.