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E V Polkoshnikov

Publications and source records attributed to E V Polkoshnikov.

11 recordsLinked to original sources
PubMed1979

[Squirrel visual cortex neurons selective for contour orientation].

The receptive field organization of orientation-selective neurons was studied in the squirrel visual cortex. Neurons with mutual inhibiting on- and off-areas of the receptive field, partially and completely overlapping excitatory and inhibitory mechanisms were observed. Neurons of the second group are the most typical. They reveal orientation selectivity if the stimuli are in the excitatory area of the receptive field, the inhibitory areas outside the excitatory area sharpen the selectivity. It is supposed that no obvious differentiation between simple and complex neurons exist in the squirrel visual cortex.

Animals↗
PubMed1975

Light-sound interaction in the neurons of the rabbit's visual cortex.

One hundred cells of the visual cortex were studied using flashes, clicks and light-sound combinations with different delays. Forty nine neurons changed the total number of spikes to click stimulation. Twenty eight cells responded to clicks with specific response pattern. In 23 cells the initial discharge occurred at 60-70 ms after the onset of clicks. In 39 cells the responses to light-sound combinations differed from the responses to flashes. While 16 cells decreased their responses, the addition of sound increased firing in 23 cells. The specific modification of the light-evoked responses under acoustic stimulation were classified into three main categories: 22 cells generated new response patterns, 18 cells showed a re-distribution of peaks in the PTS histogram and three cells demonstrated a desynchronization of the spike discharge. The study of the heteromodal recovery cycle revealed that the majority of the cells increased their firing during 0-100 ms and decreased firing during 200-300 ms of the response time scale. The critical delays between light and sound, resulting in the modification of the response for the majority of the cells, were within 100 ms in both directions.

Acoustic Stimulation↗
PubMedDate not supplied

[Responses of nervous elements of the visual cortex of the chipmunk Eutamias sibiricus to moving and stationary stimuli].

The receptive field organization of cortical units has been studied in experiments with testing by moving and stationary light spots. The size of the receptive fields varied from 3 degrees to 10 degrees. Receptive fields which were tested by a stationary light spot exhibited various types of organization. Some of the neurons produced extensive excitatory on- and off-responses to stimulation by a light spot. Neuronal excitation evoked by light decreased if the stimulus was near the field boundary. Some of the neurons produced either on- or off-responses in any point of the receptive field. A small part of neurons had receptive fields with on- and off-reactions in the center, and either on- or off-responses at the peripheral zones. Most of the neurons exhibited specialization with respect to high-speed motion.

Animals↗