The Effects of Contextual Strength on Phonetic Identification in Younger and Older Listeners

It has often been reported that older listeners have difficulty discriminating between phonetically similar items, but may rely on contextual cues as a compensatory mechanism. The present study examined the effects of different degrees of semantic bias on speech perception in groups of younger and older listeners. Stimuli from two /g/-/k/ voice onset time (VOT) continua were presented at the end of biasing and neutral sentences. Results indicated that context strongly influenced phonetic identification in older listeners; this was true for younger listeners only in the case of less-than-ideal stimuli. Findings are discussed in relation to theories concerning age-related changes in speech processing.