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V A Kurochkin

Publications and source records attributed to V A Kurochkin.

9 recordsLinked to original sources
PubMed1975

[Transcallosal modulation of the focus of maximal activity in the visual cortex].

In cats, EPs on binocular and monocular adequate stimulation in 270 symmetrical points of the visual cortex (the 17, 18, and 19 fields, and the medial portion of the suprasylvian gyrus), were studied. Charts of the maximal activity foci were drawn. Callosal transection was shown to enlarge the foci. The phenomenon of narrowing foci of maximal activity in animals with intact callosal system was found to be due to suppressing (resiprocal) interhemispherical influences increasing from the periphery towards the center of the focus. A spatial transcallosal modulation of the thalamo-cortical activation was suggested to exist in the visual cortex.

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PubMedDate not supplied

Interhemispheric asymmetry of associative responses in the cat parietal cortex.

The asymmetry of associative responses in the parietal region of the cortex was experimentally studied during visual and auditory stimulation of tubocurarine-immobilized cats at various intensities with the multiple recording of evoked potentials (EP). The left-handed asymmetry of the early and late components of associative responses was established. It was shown that the zones of convergence of visual and auditory information are also asymmetric and predominate in the left hemisphere. By contrast to the projection regions, no strength or transcallosal modulation of the interhemispheric asymmetry could be found in the parietal cortex. The data obtained indicate the applicability of the principle of functional asymmetry to the activity of paired segments of associative cortical systems in animals.

Afferent Pathways↗
PubMedDate not supplied

[An analysis of interhemispheric interrelationships in the visual cortex of cats based on the law of contrast perception of light].

The dependence of EP amplitude on the intensity of photic stimuli before and after section of the callosal body may be fully defined by the equation of the contrast law of light perception. Analysis of the nature of interhemispheric relationships by means of contrast law has shown that both reciprocal depressing and reciprocal facilitating interhemispheric relationships may exist in the primary visual cortical projection zone, and reciprocal facilitating interhemispheric influences in the secondary visual projection zone. Similarity of interhemispheric relationships has been recorded in the primary visual cortex in cats and in the secondary one, in rats, as well as in the socondary visual cortical zone in cats, and in the primary, in rats. Interhemispheric reciprocal influences in the whole range of stimuli intensities are distributed more uniformly in cats than in rats. Cats may perceive a wider range of intensity of photic stimuli than rats. In cats as in rats, the effectiveness of processing of the photic stimuli contrast is greater in the secondary visual cortical projection zone than in the primary one.

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