Auditory brainstem responses in younger and older adults for broadband noises separated by a silent gap

Wave V of the auditory brainstem response was measured to two 50-ms broadband noise bursts separated by silent gaps of varied duration (4, 8. 32, or 64 ms) for younger and older adults with normal hearing. All subjects had measurable wave V responses to the first noise burst. However, for the second noise burst. three of eight older adults did not have responses with gap durations of 4 and 8 ms. and one of eight younger adults did not have a measurable response with a gap duration of 4 ins. When responses were present for older adults, latencies were similar to those of younger subjects but amplitudes were smaller. These results suggest age-related deficits in gap detection at the level of the brainstem in a group of aged subjects with no threshold elevation. Results are similar to those of Boettcher et al. (1996) using an identical paradigm in young and aged Mongolian gerbils. (C) 2001 Elsevier Science BN. All rights reserved.