[Characteristics of the responses of auditory cortex neurons in the cat to tonal stimulation during nembutal anesthesia and after recovery from it].

Responses of auditory (AI) cortex neurons to tonal (1-25 kHz) stimulation were studied in cats under and after nembutal anaesthesia. Patterns of responses recorded during first hours and 10-30 hours after nembutal injection differed essentially. Most (89%) of neurons of anaesthetized cat had no background activity and produced stereotypical on-responses to tonal stimulation with the best frequency. Off-effects were usually absent. Variability of responses increased substantially after cessation of anesthesia. On-, on-off- and off-responses were obvious in 76% of neurons, approximately 21% of neurons tonically increased or decreased spike activity during the stimulus action. Duration of the stimulus action was reflected in response characteristics of the overwhelming majority of AI cortical neurons.