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N F Podvigin

Publications and source records attributed to N F Podvigin.

At least 37 records · Page 2Linked to original sources
PubMed1981

[Response of lateral geniculate body neurons to moving light bands in cats].

A number of electrophysiological investigations revealed that the relief of activity (RA) arising in outputs of overlapping receptive fields (RFs) of the LGB reflects the form of test image. The RA was reconstructed by the responses of single neurons. The bars' width and velocity of their movement varied. Dependence of RA size on the image size was approximated with the aid of the logarithmic function for the small angle images (less than 1.5 +/- 2.0 angle degrees) and of the power function for larger sizes. The interrelationships obtained take place within the scope of motion rates from 0.6 to 30 angle degrees per second. This scope of motion depends on the eccentricity of RFs centers in respect to the area centralis.

Animals↗
PubMed1980

[Convergence of activating connections of retinal on- and off-ganglion cells on lateral geniculate body neurons].

On- (off-) central neurons of the retina and lateral geniculate body (LGB) generate off- (on-) responses to stimuli acting upon the periphery of their receptive fields (RFs). We have found neurons with equal on- and off-responses to testing of the central part of their RFs. RFs of such neurons consist of overlapping on- and off-areas. The type of their responses can change on alteration of the stimulus parameters or under influence of light adaptation. A number of the LGB neurons seem to have activating inputs both from on- and off-central ganglionic cells of retina.

Animals↗
PubMed1977

[Relationship between the responses of neurons in the cat lateral geniculate body and the contrast in the photic stimulus].

The responses of receptive fields of the cat lateral geniculate body to stimuli of different contrast were investigated. The neuronal responses increased linearly with the stimulus contrast when the contrast change with variation in the test stimulus intensity. This relation was nonlinear when background intensity was changed. The calculation of the number of impulses in different time intervals of the response (deltat) indicated that the dependence of this number on the contrast is the steeper, the larger deltat during the first 70-90 ms of the response. The Weber-Fechner law holds for the lateral geniculate body receptive fields.

Animals↗
PubMed1976

[Response of the receptive fields of the lateral geniculate body to temporal changes in the area of a light stimulus].

Neuronal responses of the cat LGB to light spots the area of which was changing in time with different speed, were studied. All the neurons responding to switching on and off of the test spot respond to changing in time of the spot area too. The on-neurons respond to enlargening of the area while the off-neurons - to its reducing. The on- and off-responses of these fields occurred at the moment of passing of the margin of reducing (growing) spot across a certain point of neuron's receptive field. This point changed when the speed of reducing (growing) of the test spot changed.

Animals↗
PubMed1975

[Image description at the level of the external geniculate body].

The responses of the receptive fields of the cat lateral geniculate body were investigated with a different position of the light stimuli in the receptive field. The stimuli were of the cross shape. On the basis of the obtained data the relief of excitation of the overlapping receptive fields was reconstructed. It is shown that at the level of the lateral geniculate body there exist a copy of the light stimuli. The description of the image is formed as a relief of excitation which changes in time. The magnitude of the excitation depends on the contrast of the stimuli.

Animals↗