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T V Vasechko

Publications and source records attributed to T V Vasechko.

4 recordsLinked to original sources
PubMed1979

[Response of pericruciate cortex neurons to stimulation of the medial geniculate body].

Electrical responses of 239 pericruciate neurons were studied in anaesthetized and curarized cats after stimulation of the medial geniculate body and medullary pyramids. The medial geniculate body stimulation evoked in the pericruciate neurons predominantly excitatory effects in the form of increase in the mean frequency of spike activity, generation of EPSPs and EPSPs-spike sequences. The latency analysis has shown that medial geniculate neurons have mono- and polysynaptic connections with pericruciate neurons not belonging to the pyramidal tract units.

Animals↗
PubMed1975

[Synaptic processes in neurons of the cat pericruciate cortex evoked by pyramidal tract stimulation].

The influences of pyramidal tract stimulation on the activity of neurons in the pericruciate cortex were investigated on 423 neurons (81 neurons were studied intracellularly and 342--extracellularly), 78 of them having background activity. Pyramidal stimulation is shown to evoke not only antidromic spikes (0.5-16.0 ms latency) in the pyramidal cells, but also lateral and recurrent PSPs in the pyramidal and unidentified units of all cortical layers. IPSPs were observed in 46.7% of the investigated neurons, EPSPs--in 21.0%, mixed responces--in 26.0%. The latency of IPSPs was 1.5-14.0 ms, their amplitude ranged from 1.3 to 17.0 mV, the duration of the rising phase varied from 4 to 18 ms and the whole duration was 18-120 ms reaching sometimes 250-500 ms. In 30% of cases it was possible to divide the IPSPs into two phases: a fast one with a duration of 10-20 ms and a slow one. The latency of IPSPs was 2.6-19.0 ms, their amplitude--1.0--7.8 mV and duration--from 10.0 to 50.0 ms. The antidromic discharge in the pyramidal tract inhibited the background activity for 200-400 ms in 51.2% of spontaneously active units; acceleration was observed in 19.5% and mixed effect in 7.4% of units. The participation of pyramidal axonal collaterals and cortical interneurons in generation of the described processes is discussed.

Action Potentials↗
PubMedDate not supplied

Synaptic processes in pericruciate cortical neurons evoked by pyramidal tract stimulation in cats.

In cats anesthetized with chloralose and pentobarbital and immobilized with D-tubocurarine activity of 423 pericruciate cortical neurons was recorded (342 extra- and 81 intracellularly); 78 neurons had spontaneous activity. Stimulation of the pyramidal tract evoked antidromic action potentials in the pyramidal neurons with a latent period of 0.5-16.0 msec. Recurrent and lateral PSPs also developed both in pyramidal and in unidentified neurons in all layers of the cortex; IPSPs were recorded in 46.7% of neurons, EPSPs in 21.0%, mixed responses in 26.0%, and no visible changes were found in 6.3%. The latent period of the IPSPs was 1.5-14.0 msec, ther amplitude 1.3-17.0 mV, their rise time from 4 to 18 msec, and their duration 18-120 msec (sometimes up to 250-500 msec). In 30% of cases in which IPSPs appeared, their course was divided into two phases: fast (duration 10-20 msec) and slow. EPSPs developed after a latent period of 2.6-29.0 msec; their amplitude was 1.0-7.8 mV and their duration from 10.0 to 50.0 msec. In 51.2% of spontaneously active neurons the antidromic volley inhibited their activity in the course of 200-400 msec, in 19.5% it stimulated their activity, in 7.4% it had a mixed effect, and in 21.9% no visible change took place in their activity. The role and participation of axon collaterals of pyramidal neurons and of the interneuronal system in the formation of these processes are discussed.

Animals↗