The interneuronal functional associations were studied in two dogs with Nichrome semi-microelectrodes implanted into the deep layers of the motor and somatosensory regions of the cerebral cortex using the method of cross-correlation analysis. For this purpose the impulse activity of individual neurons was distinguished by form from the background multineuronal activity using the spike recognition technique. Values of a 0.5 and 1 msec-wide bin, and thereafter with a 1 msec step up to 40 msec, were used to plot the cross-interval histograms. The maximal analysis epoch was 2000 msec. The cross-interval associations were monotypal in character; they all presented fairly narrow extrema which were clearly distributed across three time ranges: short-latency associations up to 10 msec; associations with a medium latency up to 80 msec; and associations with late delays, greater than 80 msec. The fairly narrow peak of the association, especially in the case of associations with late delays, was a very difficult phenomenon to explain from the point of view of traditional theoretical perspectives. It is hypothesized that a mechanism exists in the cortex which is responsible for strictly synchronized and highly efficient synaptic transmission.

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[Role of acupuncture in bronchial asthma in children].

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[The interneuronal functional connections in the sensorimotor cortex of dogs].

Multiunit activity of sensorimotor cortex was recorded from chronically implanted semi-microelectrodes in two dogs. Functional interneuronal connections between neuronal spike trains of 6-8 neurons selected from background multiunit activity were studied by the method of cross-correlation analysis. Bin widths 0.5, 1, 2, 3 and further up to 40 ms by step of 1 ms were used. The cross-interval connections were characterized by complete absence of the shared input (central symmetrical peaks) and signs of inhibitory interrelations. The temporal interrelations between selected neurons were characterized by unilateral and bilateral non-symmetrical excitatory connections--ultra-narrow peaks with short (1-10 ms), middle (10-80 ms) and long (80-2000 ms) delays. The existence of such ultra-narrow peaks contradicts "classical" conceptions on the character of cross-interval connections based on model experiments on simple nervous systems. We suppose that special mechanism of synchronization with high temporal accuracy exists in the cortex.

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