Audiovisual speech perception in noise in younger and older bilinguals.

Abstract

Speech perception in noise becomes increasingly difficult with age. Similarly, bilinguals often have difficulty with speech perception in noise in their second language (L2) due to less developed language knowledge in L2. Little is known about older bilinguals, who experience age-related sensory and cognitive changes but have extensive L2 experience. Furthermore, while audiovisual (AV) speech cues and supportive sentence context facilitate speech perception in noise in native listeners, much less is known for bilingual listeners, particularly older bilinguals. This study investigated how much young (n = 30) and older (n = 31) French-English/English-French bilinguals benefit from AV speech cues and sentence context in their first (L1) and second language during speech perception in noise. Participants completed the task in L1 and L2. Importantly, the level of background noise was individually calibrated for each participant to equate performance during the baseline task. The results suggest that there were no age differences in overall performance during the speech perception in noise task. However, older adults showed smaller language effects and smaller modality effects (i.e., comparing auditory-only speech perception to audiovisual speech perception) compared to younger adults. Furthermore, both young and older bilinguals benefited from AV speech cues and sentence context in both of their languages. However, during L2 speech perception in noise, visual speech cues were particularly important for young adults. In contrast, older adults show equal benefit from visual speech cues in L1 and L2. Taken together, these findings extend current models of AV speech perception to a second language in both younger and older adults. Furthermore, the findings suggest that bilinguals are likely to benefit from visual speech cues and supportive sentence context, although this benefit may differ slightly between younger and older bilinguals. Public Significance StatementWhen listening to speech in background noise, having access to the speaker's lip movements and/or supportive sentence context facilitates comprehension, at least in individuals listening in their first language. Much less is known for older adults and for individuals listening in a second language, both of whom are at a greater disadvantage when listening to speech in noise (albeit for different reasons). The results from this study show that younger and older adult bilinguals benefit from seeing lip movements and from being provided with supportive sentence context during speech perception in noise in both

Adult age differences in language, communication, and learning from text.

“…Turning now to the auditory modality, Chauvin et al (2024) investigated word recognition through the perception of speech in background noise which notoriously becomes more difficult as we age (e.g., Dubno et al, 1984; Tun & Wingfield, 1999). Several factors that have been shown to improve speech perception in noise are visual speech cues that are congruent with the auditory information and a supportive sentence context.…”