The role of the temporal pole in auditory processing.

Experiments in animals have shown that the temporal pole and the amygdala are involved in auditory processing. Comparable data are scarce in humans. It is only known that after temporal lobectomy, hearing may be impaired and dichotic listening scores reduced on the ear contralateral to the operated temporal lobe. Middle-latency auditory evoked potentials (MLAEPs) and late auditory evoked potentials (LAEPs) have been recorded in 14 patients before and after temporal lobectomy for the treatment of drug-resistant temporal lobe epilepsy. The Na and Pa components of MLAEPs were significantly delayed and the Pa component amplitude reduced before and after surgery as compared to a group of 21 healthy subjects. Data in pre- and postoperative period were not statistically different. N100 and P200 component of LAEPs were similarly altered. It is concluded that in humans the amygdala and probably the temporal pole may be involved in the process of auditory activation-inhibition. The possible role of auditory processing impairment in cognitive deficits in TLE patients can also be questioned.