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R R Velikaia

Publications and source records attributed to R R Velikaia.

7 recordsLinked to original sources
PubMed1977

[Participation of hypothalamic formations in regulation of the neuronal activity of rabbit visual cortex].

Electric stimulation of different hypothalamic nuclei was used during the effect of extracellular polarizing current on neurons of the rabbit optic cortex. It was found that stimulation of the hypothalamus caused a decrease in the medium rate of impulsation of a great number of studied optic cortex neurons under conditions of anodic polarization when the background level of activity was considerably enhanced. The same stimulation increased the activity under conditions of cathodic polarization when the initial level of the activity was considerably lowered. The same tendency to restore the initial (background) level of the neuronal activity after hypothalamic stimulation was observed under conditions when this level was shifted by application of rhythmic light. The greatest effect was observed during stimulation of the preoptic region. Stimulation of the posterior hypothalamic nucleus was less effective in this respect.

Animals↗
PubMed1975

[Influence of the hypothalamic nuclei on the electrical activity of neurons of the visual cortex].

Background and light-evoked activity of single neurons in the rabbit optic cortex was investigated before and after electrical stimulation of the anterior and posterior hypothalamic nuclei. No distinct reciprocity between the effect of the anterior and posterior hypothalamic areas on the optic cortex neurons was found. Long cyclic changes in the background rhythmic activity of the neurons were observed after stimulation of different hypothalamic nucleima modulating effect of these nuclei on the activity of the optic cortex neurons was also detected under conditions of retinal stimulation by repetitive light.

Animals↗
PubMedDate not supplied

[Organization of the background activity of rabbit visual cortex neurons].

Algorithm of calculation of consitent approximation to real entropy and redundancy which helps to understand the connection of two or more related states was realized by means of electronic computer BECM-6. Different laws of changes of information estimates dependeing on the number of approximation and the pitch of temporary quantum of messages corresponded to every type of cell impulsation of rabbits' visual cortex--arrhithimical, grouping and regular. The connections between the laws of impulse succession organization and some of its parameters were revealed. The results of studying the models of casual and deterministic pulse trains were compared.

Animals↗
PubMedDate not supplied

[Patterns in the reaction of rabbit visual cortex neurons to constant illumination].

A number of informational estimates for the reactions of excitation, inhibition and of A-type (according to Young) of rabbits' visual cortex neurons to constant light was calculated by means of electronic computer -6. It has been found that entropy as well as redundancy are sometimes the characteristics of reactions intensity: the correlation of their values is regularly connected with the type of reactions. Possibility of optimal (for exposing the reactions) quantization of records with respect to time was shown. The regularities of "thin" statistical reactions' structure consisting in the change in "force" and "distance" of intercennection action were found. Possible informational value of the obtained results is discussed.

Animals↗