Physiological mechanisms in auditory brainstem-evoked response.

A critical review is presented of the physiological background for the interpretation of ABR auditory brainstem response). The importance of the transformation of the monophasic click stimulus to a dampled oscillation on the basilar membrane, the travelling wave velocity and the synchronization of high frequency units in the auditory nerve are emphasized. The ABR is an expression of the wave front of the leading volley of synchronized action potentials generated in nerve cell bodies in the relay stations of ascending auditory pathway. It is concluded that the physiological evidence for IC as sole, or main generator of wave V is very incomplete. The possibility of multiple generators in the SOC-complex is emphasized.