Abstract:

Sommers [M. S. Sommers, J. Acoust. Soc. Am. 101, 2278--2288 (1997)] has recently demonstrated significant declines in both talker normalization and lexical discrimination in older listeners and suggested that these deficits contribute significantly to age-related impairments in speech perception. The present set of investigations were designed to: (1) determine whether individual differences in talker normalization and lexical discrimination are related to the speech perception abilities of older adults assessed under a variety of listening conditions; and (2) examine whether age changes in the two abilities are related to deficits in more general cognitive capacities. Results to date suggest that individual differences in talker normalization and lexical discrimination account for a significant percentage of the variance in speech perception scores among older listeners. In contrast, performance on tests of working memory, general intelligence, and selective attention were largely unrelated to either of the two abilities. The overall patterns of findings suggests that talker normalization and lexical discrimination are independent components of the speech perception system that exhibit considerable individual variation in the extent to which they are preserved in older adults. [Work supported by the Brookdale Foundation.]