Grant: Operating Grant

With notable exceptions (e.g., communicating by telephone), a person can both hear the speech signal and see the speech cues produced by his/her communication partner. Using auditory and visual speech information (i.e., lipreading) to understand speech is referred to as audio-visual (AV) speech perception. Both normal-hearing and hearing impaired persons perform markedly better on AV speech perception tasks than on auditory (A) or visual (V) tasks alone. This is ecologically advantageous because speech perception typically takes place in less than ideal acoustical environments (e.g., noise, etc.). Recent studies of AV speech perception in older adults have left many issues unresolved. We will investigate the AV speech perception abilities of healthy young and older adults. Our short-term objectives are to describe and understand aspects of bimodal (auditory and visual) speech processing and integration by investigating the sensory, perceptual, and cognitive processes involved in AV speech perception. Our long-term objectives are to understand the individual differences that contribute to AV speech perception and the brain mechanisms that which underlie the integration of speech signals. Given the importance of communication in society, our research promises to address quality of life issues for elderly individuals, many of whom have hearing loss (estimated at more than 60 % among individuals aged 75+ years). Our results may inform guidelines for communication strategies that could be used by and intervention programs that could be developed for older persons with communication difficulty due to hearing/visual disabilities or cognitive impairments/declines. Finally, our results should provide information for models of bimodal speech-perception across the lifespan.