[Inhibitory interneuronal interactions in microregions of the visual cortex].

The interactions between the neighbouring neurones of the visual cortex were studied in the background multineuronal activity of awake cats and of cats anaesthetized with Nembutal. The experiment was carried out on 64 trineuronal microsystems with the method of cross-correlation analysis. Those histograms of cross-correlation were analyzed, in which the parameters and configuration seemed to be determined by inhibitory interneuronal interactions. It is assumed that this inhibition is achieved via recurrent axonal collaterals. The duration and the intensity of inhibitory effect, observed in anaesthetized cats, greater than those in awake animals, may be due to a decrease in the general excitatory synaptic drive and to blocking of the unspecific brain system by Nembutal.