Effect of band-limited clicks on ABR waves I and V

Studies have shown that the I-V latency difference decreases in cases of high-frequency peripheral loss. In order to limit the variability associated with a hearing-loss population, we studied this latency decrease using normal-hearing young adults. Listeners were exposed to band-limited clicks having differing low-pass cutoffs. Responses to the low-pass clicks were intended to duplicate the ABRs that would be evoked by wide-band clicks in ears with high to mid-frequency hearing loss. The clicks were presented in both polarities. The primary finding was that the low-pass rarefaction clicks produced disproportionately large increases in wave I latency as low-pass cutoff frequency was reduced, i.e., as "hearing loss" extended into the mid-frequencies. This finding appears to explain, at least for the conditions of study, the shortening of the I-V interval with peripheral hearing loss.