The Effect of Efferent Nerve Stimulation upon AP during Intense Sound Exposure

Abstract

In order to investigate the effect of olivocochlear bundle (OCB) upon the AP during intese sound exposure, a total of 42 albino guinea pigs were expored to 2 KHz pure tone at 100 dB SPL, 120 dB SPL and 130 dB SPL with or without electrical stimulation of OCB, and the AP threshold and amplitude were evaluated between two conditions. In OCB stimulation groups (110 dB SPL for 30 min. 120 dB SPL for 30 min.), the AP threshold shift was smaller than in control groups. The AP amplitudes were reduced after intense sound exposure in both OCB stimulation groups and control groups. The results obtained in the present study indicate that OCB has a protective role to the cochlea in casa of intense sound exposure.