Cochlear Processes: a Research Report

This paper summarizes recent research on functions of the cochlea of the inner ear. The cochlea is described as the seat of the first step in the auditory sound analysis and transduction of mechanical vibration into electrochemical processes leading to the generation of neural action potentials. The cochlea is also described as a frequent seat of auditory disorders. This research summary addresses findings concerning: the classical model of cochlear functioning developed by ter Kuile and modified by H. Davis; explanations for the sharp tuning and great sensitivity of the auditory nerve fibers and inner hair cells; the role of the outer hair cells in cochlear acoustic emissions; contradictions of the classical model of hair cell stimulation posed by evidence for the depolarization of the hair cells during basilar membrane displacement; effects of removing the outer hair cells; possible mechanisms for hair cell depolarization; increased damping of th.i cochlea at high sound intensities; and the nature of the cochlear pitch code. Figures and graphs illustrate these findings. Contains 49