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Biomedical subjects

V F Fokin

Publications and source records attributed to V F Fokin.

At least 37 records · Page 2Linked to original sources

[Physical criteria of pathological processes. I. Change in the functional hemispheric asymmetry at various stages of rheumatic diseases].

The functional interhemispheric asymmetry of brain in patients with systemic rheumatic diseases was estimated by measuring brain direct current potentials. It is shown that different types of functional interhemispheric asymmetry correspond to different stages of systemic rheumatic diseases. At early stages, the left hemisphere asymmetry dominates, at expressed stages, the right hemisphere asymmetry is prevalent, and the terminal stage is characterized by the loss of functional interhemispheric asymmetry.

Brain↗

[Synchronization of changes in the level of direct current potential and concentration of lipid peroxidation products in the developing rat brain].

The dynamics of the level of direct current potentials and the content of lipid hydroperoxides, conjugated dienes, Schiff bases of phospholipids and lipofuscin in the brain of rats during ontogenesis was studied. It is shown that changes in neurophysiological and biochemical characteristics have an M-shaped character. The synchronization of age-dependent changes in the content of lipid peroxidation products and the dynamics of direct current potentials was revealed.

Aging↗

[The characteristics of the slow electrical activity of the brain in those who worked in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station].

We studied the slow electrical activity of the brain in people subjected to irradiation as a result of the Chernobyl accident and in healthy donors. The mean constant potential, which is an index of energy metabolism in different regions of the cerebral cortex, is reliably lower in eliminators, as compared to the donors, thus suggesting a postradiation energy deficiency of the brain. The structure of correlations between the constant potential indices is different: the number of significant correlations in the group of eliminators is lower by 30% than in the group of donors, thus suggesting disturbed intercentral relations in the CNS under the conditions of postradiation energy deficiency of the brain.

Brain↗

[Systemic organization of functional interhemisphere asymmetry. Mirror asymmetry].

The systemic organization of hemispherical asymmetry at the behavioral, neurophysiological, and biochemical levels was studied. An interconnection and hierarchic coordination of the parameters of different levels were revealed, which are confirmed by multiple correlations between them. An interrelation between the processes of peroxidation of brain membrane lipids, the level of direct current potential, and the behavior of animals was shown. A significant difference in correlations between right-hander and left-hander animals was found.

Animals↗

[Dynamics of functional interhemisphere asymmetry and sexual dimorphism in rat ontogenesis].

The dynamics of functional interhemispherical asymmetry in the ontogenesis of rats, males and females separately, was studied. The asymmetry was determined by the neurophysiological criterion, the interhemispherical gradient of the distribution of direct current potential of the brain. The sexual dimorphism upon age-related changes in the interhemispherical asymmetry was shown. It is assumed that this asymmetry is involved in the dynamics of neuroendocrine interactions determined by sex.

Animals↗

[Dose-dependent tazepam modulation of amplitude-temporal characteristics of thalamocortical responses and the constant potential of the sensorimotor cortex in rabbits at eye opening].

The pronounced benzodiazepine (antiphobic) modulation of the amplitude-temporal parameters of different components of the thalamocortical responses (TCR) of the sensorimotor cortex is observed in rabbits in their early postnatal ontogeny. This modulation is of a dose-dependent character and is registered not after the injection of tazepam in a concentration of the "therapeutic tranquilizing window" but also in the psychotoxic plasma range. A gradual increase in blood tazepam concentration in a young rabbit pup is accompanied by the wave-like and differential decrease in the amplitude of the second and third positive (P2 and P3) and third negative (N3) TCR components, while the second negative (N2) and fourth positive (P4) components tend to a wave-like increase. The dose-dependent dynamics of tazepam modulation of the P2, P3, and N3 latencies is characterized by a wave-like and differential increase. The latency of P4 decreases slightly and that of the N2 increases with a low degree of significance. The selective dynamics of benzodiazepine modulation appears to be related with peculiarities of the electrogenesis of each of the components. The dose-dependent modulation of the level of cortical DC potential is of the same character as the respective amplitude changes in P2, P3, and N3, but its fluctiatuons are more pronounced.

Animals↗

[The dynamics of forming an active defensive reflex in cats].

Active defensive reflexes were elaborated in cats with pain stimulations of the forepaw by means of an electrical pricking device with a target attached to it. The elaboration was carried out during action of a flickering light used for the convenience of the EEG analysis. Repeated pain stimulation led to elaboration of an aggressive attacking reaction, chiefly manifested in the paw striking the target. At the beginning of the elaboration, passive-defensive reactions were manifest, which did not completely disappear even after formation of a stable attacking reflex. Two types of active defensive reflexes were elaborated: A-type reflex which helped the animal to get rid of the pain stimulation at the very beginning; B-type reflex which prevented the pain stimulation. The difference beteween these two types is discussed.

Aggression↗

[The dynamics of the direct current potentials of the brain during sustained attention in 10-11-year-old children].

The dynamics of direct current potentials of the brain was studied in 10-11-year-old children during sustained attention to successive presentation of series of Shulte tables. Children were examined twice: before and after the series of training to fast reading. A gradual increase in the level of direct current potentials during sustained attention was observed. The increase was more pronounced in children with excessive than in children with moderate reactions to the loading. After the series of training to fast reading, the increase in the level of direct current potentials was reduced in both groups. This aftertraining neurophysiological phenomenon was combined with a transformation of psychophysiological characteristics: a decrease in the time of viewing of Shulte tables and increase in the speed of reading. It is suggested that the shifts of direct current potentials reflects the dynamics of intensity of the cerebral energy metabolism.

Attention↗