Long-term sensorineural hearing loss induces functional changes in the rat auditory nerve

Abstract

Loss of cochlear hair cells in the rat initiates degenerative change within the primary auditory neurons (ANs) of the cochlea. These degenerative changes include loss of peripheral processes, demyelination and ultimately cell death. This pathology will affect the biophysical processes involved in action potential generation and propagation to an electrical stimulus via a cochlear implant. We measured the response properties of ANs, with particular reference to their refractory behaviour, in normal, short- (9 weeks) and long-term (> 52 weeks) deafened rats. AN loss was moderate in the short-term and severe in the long-term deafened animals. AN activity was elicited using a brief electrical st..