Recognition of asynchronous auditory-visual speech by younger and older listeners: A preliminary study.

This study examined the effects of age and hearing loss on recognition of speech presented when the auditory and visual speech information was misaligned in time (i.e., asynchronous). Prior research suggests that older listeners are less sensitive than younger listeners in detecting the presence of asynchronous speech for auditory-lead conditions, but recognition of speech in auditory-lead conditions has not yet been examined. Recognition performance was assessed for sentences and words presented in the auditory-visual modalities with varying degrees of auditory lead and lag. Detection of auditory-visual asynchrony for sentences was assessed to verify that listeners detected these asynchronies. The listeners were younger and older normal-hearing adults and older hearing-impaired adults. Older listeners (regardless of hearing status) exhibited a significant decline in performance in auditory-lead conditions relative to visual lead, unlike younger listeners whose recognition performance was relatively stable across asynchronies. Recognition performance was not correlated with asynchrony detection. However, one of the two cognitive measures assessed, processing speed, was identified in multiple regression analyses as contributing significantly to the variance in auditory-visual speech recognition scores. The findings indicate that, particularly in auditory-lead conditions, listener age has an impact on the ability to recognize asynchronous auditory-visual speech signals.