[Intracellular reactions of neurons of the primary auditory area of the cerebral cortex in the cat to tones of different frequency and electric stimulation of nerve fibers of the spiral ganglion].

In experiments with nembutal-anaesthetized cats it was found that neurons in the AI auditory cortical area responded to sound stimulation by EPSP, EPSP-spike-IPSP, EPSP-IPSP and IPSP. The majority of neurons studied responded to tones of characteristic frequency or to above-threshold tones whose frequencies were close to the characteristic ones as well as to electrical stimulation of spiral ganglion fibres innervated a central part of the receptive field by the sequence: EPSP-spike-IPSP. Tones whose frequency differed significantly from the characteristic one and electrical stimulation of the peripheral parts of the receptive field evoked responses in the form of EPSP-IPSP or IPSP. The tone frequency band that under threshold stimulation evoked a spike in a neuron was significantly narrower than the tone frequency band that evoked EPSP or IPSP. Two types of IPSPs were observed: components of the EPSP-spike-IPSP sequence evoked by excitation of receptors in the centre of the receptive field and primary or following EPSP evoked only if receptors locating in peripheral parts of the receptive field were excited.