The Effects of Aging and Interaural Delay on the Detection of a Break in the Interaural Correlation between Two Sounds

Abstract

The age-related decrease in sensitivity to a BIC indicates that older adults are less able than younger adults to detect a change in correlation in an ongoing sound. The inability of older adults to detect the 100 ms BIC as readily as younger adults, when the noise arriving at one ear is delayed relative to the noise arriving at the other ear, suggests that the representation of aspects of the sound's waveform decays more rapidly in older adult than in younger adult listeners. Moreover, these age-related deficits are not related to listeners' audiograms. In addition, younger adults seem to be much better than older adults at using the spectral cue provided by comb filtering to detect the BIC when there is a delay between the noises presented over loudspeakers. The more rapid decay of waveform details, combined with the lesser sensitivity to change in correlation and to spectral cues, suggest that older adults may not be as capable as younger adults in parsing auditory scenes.