[Effect of proprioceptive and visual stimulation on brain stem auditory evoked potentials in the cat and in man]

Proprioceptive effect on the activity of different levels of the auditory system was studied in cats under Nembutal anaesthesia and in humans, by means of recording brain stem auditory evoked potentials - BAEPs (in response to cliks), whose consecutive waves correspond to successive levels of the auditory system. BAEPs were compared when the head was in a straight position and when it was turned 45 degrees to one side. The turns elicited changes in amplitudes and latencies of all BAEP waves similarly in cats and humans but in different combinations and in different directions, which points to plurality and heterogeneity of proprioceptive effects at different auditory levels. Analogous effect on BAEPs was produced by photic stimulation - illumination of one eye in cats and of the experimental chamber in humans. The character of the effects suggests participation of the activity of descending auditory paths and the cerebellum.