Abstract:
The basilar membrane (BM) in the cochlea separates out the frequency components of sounds. Different places on the BM are tuned to different frequencies. The tuning is enhanced by an active mechanism that effectively amplifies the BM response to low-level sounds over a narrow range of frequencies at each place. This results in a shallow (i.e., compressive) input/output function. Loss of the active mechanism is the main underlying cause of hearing impairment, resulting in a loss of sensitivity to quiet sounds, a rapid growth of loudness with sound level, and an inability to separate sounds due to the reduction in tuning. The talk will describe recent behavioral measures of the BM response function, in individuals with normal and impaired hearing.