Effect of age on clear speech intelligibility.

Abstract

Previous work has established that elderly adult’s comprehension is more detrimentally affected by noise, multi-talker babble and the absence of contextual cues compared to younger adult’s comprehension. Elderly adult’s abilities to understand fast speech and to detect/recognize brief non-speech and speech sound sequences (e.g., stop gaps) also decline with age. These effects seem to persist even when hearing loss is taken into account. In this study, we explored whether there are parallel effects of age on speech production, i.e., whether elderly adult’s production patterns differ from those of younger adults. Specifically, we examined whether elderly and younger adult’s hyper-articulation clear speech strategies provide similar intelligibility advantage for younger adult listeners. The sentence-in-noise perception results revealed that elderly adult’s clear speech increased intelligibility for young adult listeners. Importantly, the overall elderly adult’s speech intelligibility and the clear speech intelligibility gain were smaller compared to that provided by the speech of younger adults. Acoustic correlates of the differences in the observed clear speech gain provided by older and younger adults are explored. These results suggest that, in addition to perceptual problems, cognitive and hearing changes due to age can affect elderly adult’s speech patterns and intelligibility.