COCHLEA FREQUENCY-POSITION FUNCTION OBTAINED FROM ATTENUATION CHARACTERISTICS OF BASILAR MEMBRANE WAVE

Abstract

This study focuses on the attenuation characteristics of the wave that propagates on the basilar membrane. The basilar membrane wave, which occurs from the interaction between the basilar membrane and fluid, plays a major role in the hearing system. Because the mass and stiffness of the basilar membrane are graded along its length, the basilar membrane wave peaks at a specific region along the cochlea depending on the acoustic wave frequency. We took the viscosity of the fluid into consideration and investigated the wave characteristics by conducting modal analysis. We found that the attenuation curve of the basilar membrane wave has an inflection point and the frequency-position function obtained from the inflection points matches well with the Greenwood function. This suggests that the mode of the basilar membrane wave drastically changes before and after the peak point.