Place specific influences on the wave I to V interpeak latency of the auditory brain-stem response.

There is controversy over whether the wave I to V interpeak latency (I-V IPL) of the auditory brain-stem response can be manipulated by cochlear processing. In this study, a forward masking paradigm was used to test the predictions of two contrasting models of I-V IPL generation. The paradigm was designed to determine if the I-V IPL can be affected by masking selected portions of the cochlear response region. The results from ten normal hearing subjects suggest that: (1) waves I and V can be masked semi-independent of each other, and (2) the I-V IPL can be shortened or prolonged by masking the basal or apical portion of the cochlear response region respectively. These findings support the hypothesis that, at least in normal hearing subjects, wave V is biased to reflect more apical cochlear events than wave I. Additionally, they offer tentative support for anecdotal reports of shortened I-V IPLs in the presence of high-frequency hearing loss.