Intracranially recorded responses from the human auditory nerve: new insights into the origin of brain stem evoked potentials (BSEPs).

Auditory evoked potentials were recorded intracranially from the 8th nerve during neurosurgical procedures. The potentials had a large negative peak that occurred 3.0--3.7 msec after the onset of the stimulus (2 000 Hz tone bursts). When these potentials were compared with the scalp recorded brain stem evoked potentials (BSEPs) the intracranial response was found to match the latencies of the P2N3 complex of the BSEP. The results are interpreted as showing that the neural generator of the second peak of the BSEP is the intracranial portion of the auditory nerve and not, as was earlier assumed, the cochlear nucleus.