Abstract: | Responses of 141 neurons of the caudate nucleus to acoustic stimuli — tones (500 and 2000 Hz) and clicks of different frequency (0.2 and 0.8/sec) and intensity (75, 80, 95 dB) — were recorded extracellularly in chronic experiments on cats. The responses recorded showed great variability with respect to character (phasic, tonic), structure (one or two phases of excitation), latent periods (from 7.5 to 300.0 msec), and burst discharge frequency (from 90 to 800 spikes/sec). Analysis of averaged poststimulus histograms and graphs of the dynamics of the responses showed that responses of 74% of neurons were much better expressed if less frequent stimuli were used: The regularity of the responses and the number of spikes in each response increased. Responses of neurons also increased and acquired a more distinct temporal structure if the intensity of the clicks increased. The character of responses to clicks and tones differed qualitatively in 17% of neurons studied: Phasic excitation arose in response to clicks, tonic changes in spike activity to tones. The particular features of responses of caudate neurons to acoustic stimulation with different parameters are discussed.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 12, No. 6, pp. 588–595, November–December, 1980. |