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A A Aĭrapetian

Publications and source records attributed to A A Aĭrapetian.

4 recordsLinked to original sources
PubMed1977

[Effects of electric stimulation of the dentate nucleus of the cerebellum on neuronal activity of the centrum medianum of the optic thalamus].

Electrical stimulation of the cerebellar dentate nucleus elicits in neurons of the center median responses with either constant or altering latencies. The constant latencies ranged from 2-3 to 8-12 msec. Responses with altering latencies were more numerous and had the latencies up to 20 msec. In both responses with early and late components were recorded as well. Dentate stimulations induced "periods of inhibition" in CM neurons with leading duration of 50-100 msec. Synchronization of the SM unit activity during low-frequency stimulation was also revealed, in many cases it was preceded by the "periods of inhibition". Activity of 49% of reactive neurons during 1, 7-12, and 70-100/sec stimulations was facilitated, 31% depressed, and 20% had a mixed type of responses: facilitation on one frequency and depression on another. Immediate cessation of the effects after termination of stimulations was observed in 34% of neurons, while tonic influences were manifest in 66%.

Animals↗
PubMedDate not supplied

[Responses of sensomotor cortex neurons of rats to stimulation of the midbrain reticular formation].

High frequency stimulation of the mesencephalic reticular formation produces significant inhibition of neuronal activity in the sensorimotor cortex, the effect being equally observed in both hemispheres. In case of low frequency stimulation, marked difference was observed between the reaction of ipsi- and contralateral neurons. Under these conditions, contralateral neurons produce mainly facilitation responses. In both hemispheres evident predominance of tonic effects was observed which revealed itself in the continuation of the reaction in the poststimulation period. Single shocks applied to the midbrain reticular formation elicited in the cortex the evoked potentials of two types: one with a constant and the other with varying latent periods. The former exhibited a latency of 4-18 msec. Responses with varying latencies were predominant. In general, latent periods were longer in contralateral hemisphere.

Animals↗