Abstract - Wroblewski

Development of multisensory integration in noisy and reverberant listening conditions: linguistic and cognitive predictors in school age children

Abstract: Elementary school classrooms that meet the acoustic requirements for near-optimum speech recognition are extremely scarce. Poor classroom acoustics may become a barrier to speech understanding as children enter school. Although young school-age children who are developing speech, language, and learning skills require a favorable acoustic environment to achieve near-optimum speech recognition performance, their classrooms tend to be noisy and reverberant, often more so than those of their older peers. To learn and communicate in noisy and reverberant environments, children must come to integrate auditory and visual speech information. In less than optimal environments, visual speech information is an important aid for speech recognition and it may be especially important for children given that their ability to recognize speech in noise and reverberation does not reach maturity until the teen years. Although, a number of attempts have been made to document the development of auditory-visual integration in children, there are important gaps in our knowledge base. First, the extent to which speech-reading assists children with the recognition of speech in noisy and reverberant environments typical of elementary school classrooms has yet to be fully appreciated. Second, some words are harder to recognize than others even when presented in the same listening environments, and the effect of such lexical difficulty on multisensory integration in these less-than-ideal listening conditions is not known. Third, as mechanisms of multisensory integration develop, so too do linguistic and cognitive abilities and little is understood about the relationship between these concurrently developing systems. This project seeks to address these gaps in the knowledge base. The specific aims are to 1) determine the extent to which reverberation affects speech-reading benefit during speech perception in noise by school-age children; 2) quantify the speech-reading benefit for "easy" relative to "hard" words presented in noise and reverberation; 3) elucidate the relationship between cognitive and linguistic development and speech-reading benefit in noise and reverberation. Speech-reading benefit will be assessed via the difference between the signal-to-noise ratio required for 70% correct performance for auditory-only and auditory-visual presentation modes in low, moderate and high reverberation, with the use of low-context sentence materials containing keywords with variable level of lexical difficulty. Cognitive and linguistic skills will be examined using the Cognition Battery of NIH Toolbox. The results of this study will shed light on the development of speech-reading benefit in noise and reverberation during the school years, and provide insight into the cognitive and linguistic underpinnings necessary for auditory-visual integration of degraded speech. The long-term goal of the proposed research project is to advance evidence-based and ecologically-valid pediatric clinical speech recognition testing, help define possible linguistic and cognitive barriers to children's learning in adverse listening conditions, and help develop strategies to overcome these barriers. (Marcin Wroblewski, collaborating with Karla McGregor and Ruth Bentler).