[Types of correlative relations of the neuronal impulses of the visual and sensomotor areas of the neocortex in the rabbit].

Neuronal activity of the visual and sensorimotor cortical areas was simultaneously recorded in intersignal intervals in rabbits with conditioned reflexes to light and sound. ES-1020 computer built cross-correlation (CCH) and autocorrelation (ACH) histograms of impulse activity of the se neurones. Analysis of CCH form, built with a bin of 2 ms gave no convincing proofs of the presence of synaptic connections between neurone of the visual and sensorimotor cortical areas and of influences from a common source with few switchings on interneurones. Analysis of CCH built with bins of 10 and 30 ms, allowed to single out primary and secondary peaks and troughs. Wide primary peaks with the base covering the beginning of the coordinates, were met in 51.9% of cases; wide peaks, greatly shifted relatively to the coordinates beginning,--in 40.9% and trough--in 7.2% of cases. Secondary peaks did not always reproduce the ACH form of impulses trains of recorded neurones. The CCH analysis allowed to suggest two basic mechanisms, eliciting the correlated discharges--action of common input and influence of the neurones of one area on the other through a number of interneurones. It was not always possible to separate these two cases by means of CCH. In a number of cases, a more complicated character of neurones interaction could be suggested.