Single unit responses recorded from the first order neuron of the pigeon auditory system.

Intracochlear recordings from the first order neurons in the eighth nerve of the pigeon were made with microelectrodes. The basic response characteristics of the single units were similar to those recorded from mammalian first order auditory neurons with the following exceptions: units responding solely to 'sweep frequencies' were found and one unit was found for which the rate of discharge decreased with increased intensity. Suppression of spontaneous activity during tonal stimulation was found within the response curve of the unit and for frequencies beyond the boundaries of the response curve. In addition, suppression of spontaneous activity was found after the termination of the tone. The amount of suppression and the recovery process varied considerably from unit to unit. The controlling variables were intensity and duration of the stimulus.