Speech-evoked ABR: Effects of age and simulated neural temporal jitter.

Speech-evoked ABR: Effects of age and simulated neural temporal jitter.
Hear Res. 2015 Sep 11;
Authors: Mamo SK, Grose JH, Buss E
Abstract
The speech-evoked auditory brainstem response (sABR) provides a measure of encoding complex stimuli in the brainstem, and this study employed the sABR to better understand the role of neural temporal jitter in the response patterns from older adults. In experiment 1, sABR recordings were used to investigate age-related differences in periodicity encoding of the temporal envelope and fine structure components of the response to a/da/speech token. A group of younger and a group of older adults (n=22 per group) participated. The results demonstrated reduced amplitude of the fundamental frequency and harmonic components in the spectral domain of the recorded response of the older listeners. In experiment 2, a model of neural temporal jitter was employed to simulate in a group of young adults (n=22) the response patterns measured from older adults. A small group of older adults (n=7) were also tested under the jitter simulation conditions. In the young adults, the results showed a systematic reduction in the response amplitude of the most robust response components as the degree of applied jitter increased. In contrast, the older adults did not demonstrate significant response reduction when tested under jitter conditions. The overall pattern of results suggests that older adults have reduced neural sy...

Source: Hearing Research - September 11, 2015 Category: Audiology Authors: Mamo SK, Grose JH, Buss E Tags: Hear Res Source Type: research