Modeling temporal effects in two-tone suppression

Abstract

The medial olivocochlear reflex (MOCR) reduces the gain of the active process in the cochlea. Both physiological and psychoacoustical data support the hypothesis that the MOCR may improve the response to a tone in noise. This is generally interpreted as resulting from a decrease in the response to the noise. However, elicitation of the MOCR may also reduce suppression, an instantaneous cochlear gain reduction that is a by-product of the cochlear active process. There is only limited physiological and psychoacoustic data on the effect of the MOCR on suppression. Recently, the time-course of the MOCR has been integrated into a well-established computational auditory nerve model [Smalt et al., J. Assoc. Res. Otolaryngol. (2013)]. The purpose of this study is to use the auditory nerve model to systematically examine suppression and the effects of the MOCR at the level of the basilar membrane and the auditory nerve. These results will provide more understanding on the interaction of these two types of gain reduction and how they relate to speech understanding in noise. [Research supported by NIH(NIDCD) R01 DC008327 and T32 DC00030.]