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T I Luchkova

Publications and source records attributed to T I Luchkova.

11 recordsLinked to original sources
PubMedDate not supplied

[Effect of anodal polarization of several subcortical structures on the spatial synchronization of cortical potentials during elaboration of a defensive conditioned reflex in rabbits].

The effect of the functional state of some thalamic and hypothalamic nuclei, modified by anode polarization, on spatial synchroneity of cortical potentials (SSCP) and the speed of elaboration of a conditioned defensive reflex (CDR) were studied in chronic experiments on 15 rabbits. Reversible blockade of the studied subcortical structures considerably affected the local SSCP form and the reflex execution. In intrasignal periods the global SSCP practically did not change. A comparative analysis of the results permits an assumption that the mammillary bodies play an important role in the formation of local SSCP at the beginning of defensive conditioning and that in the stabilized reflex, this SSCP form requires the activity of non-specific thalamic nuclei.

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PubMedDate not supplied

[The interhemispheric brain asymmetry of the rabbit in a state of "animal hypnosis"].

By the method of forced immobilization the rabbits were brought into the state of "animal hypnosis" (immobilization reflex), and their ECoG was recorded, which was further processed on the computer. It was found that during hypnosis a functional interhemispheric brain asymmetry was developed in rabbits with activity predominance in the right hemisphere. The "animal hypnosis" is a phasic process: in the ECoG of the rabbit under hypnosis a regular alternation of delta and theta activity takes place. Electrophysiological reconstructions in the rabbit brain during the change of its functional state correlate with the brain thermal reactions, revealed earlier.

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PubMedDate not supplied

[The ECoG of rats with genetic catalepsy].

Electrographic study was carried out in Wistar rats and the rats of genetical catalepsy (GC) strain. In contrast to Wistar rats epileptiform activity was observed in ECoG of GC rats being enhanced at the transition to a cataleptic state. Analysis of spectra and coherence of EEG revealed the presence of interhemispheric brain asymmetry in all the rats. In some frequency bands in GC rats inversion of interhemispheric asymmetry was found, which had been characteristic for Wistar strain. The highest interhemispheric synchronization of biopotentials was observed in the frontal cortical areas in GC rats and in the occipital areas in those of Wistar strain.

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PubMedDate not supplied

[Spatial organization of the electrical potentials of the brain in the rabbit during low-frequency electric stimulation of subcortical structures].

The influence of low-frequency (2-9 Hz) electric stimulation of some limbic system structures (mammillary bodies (MB), field CA1 of the dorsal hippocampus, subiculum), thalamus midline nuclei on spectral-correlative characteristics of potentials of the neocortex and some subcortical formations and elaboration of the defensive conditioned reflex (CR) was studied in 19 rabbits. Electric stimulation of all studied formations with the current of 0.1 mA and 2-4 Hz frequency contributed to the appearance of delta-rhythm in the neocortex, especially highly expressed when MB was stimulated at the beginning of CR elaboration. The appearance of delta-rhythm in the neocortex and other examined structures impeded CR elaboration; during MB stimulation with a frequency of 2-4 Hz, CR could not be elaborated. The most favourable conditions for maintaining the theta-rhythm and CR elaboration were established when each of the examined structures was stimulated with frequency of 7 Hz, but CR elaboration was not accelerated.

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PubMedDate not supplied

[Spatial synchronization of brain potentials during extinctive inhibition].

The changes in spatial synchroneity of potentials in the cortex (SSCP) and several subcortical structures (some nuclei of the hypothalamus and non-specific nuclei of the thalamus) were studied in 11 rabbits in the course of extinction of defensive conditioned reflex (CR) to light. In the course of extinction, at the movement of the non-reinforced stimulation, specific increase in SSCP gradually disappears and the synchroneity between the cortex and subcortical structures decreases. In intersignal periods, at the stage of complete extinction, SSCP returns to the values prior to CR elaboration. The obtained data suggest that during CR extinction, a discrepancy of functional states gradually develops both between different cortical areas and between the cortex and the studied subcortical structures.

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