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Biomedical subjects

N V Bratus'

Publications and source records attributed to N V Bratus'.

At least 19 recordsLinked to original sources
PubMed1992

[Role of the frontal cortex in the organization of rapid ballistic movements of rats].

Rapid ballistic food-getting movement characteristics were studied in albino rats. After ablation of the second area of the frontal cortex contralaterally as to the preferred extremity the number of attempts increased and their duration with reorganization of the phase structure of movements decreased. The habit of food extraction was lost after bilateral ablation of the cortex. The obtained results have illustrated significance of the frontal cortex in formation and realization of moving programmes.

Animals↗
PubMed1987

[Comparative physiologic study of the responses of cerebellar cortex neurons to stimulation of the vagus nerve].

The cerebellar cortex neuronal responses (of Purkinje cells--PC, and of unidentified neurons UN) to vagus stimulation in anesthetized pigeons, rats and monkeys were actualized as spikes or as complex discharges in PC. Tonic neuronal responses were mainly excitatory. All the PC and the majority of UN were polymodal. Differences in the line: birds--mammals, started with an increase of responsiveness, particularly on account of mossy fibers input. A shortening of neuronal responses latency was observed. In monkeys only, a lengthening of inhibitory pauses and a variability of afterdischarges were found. The significance of cerebellum in interoceptive information processing seems to increase in phylogenesis.

Animals↗
PubMed1982

[Interaction of automatic centers].

Evoked responses in the cerebellar cortex during stimulation of posterior hypothalamus in anesthetized cats revealed activating as well as inhibitory influences on the cerebellar cortex. The mamillary med. nucleus seems to have monosynaptic as well as polysynaptic connections. The principal connections of the posterior hypothalamic nuclei are polysynaptic. The supramamillary nucleus has both oligosynaptic (to neocerebellar cortex) and polysynaptic (to vermal cortex) connections.

Animals↗
PubMed1981

[Electrical responses of the red nucleus to acoustic stimulation].

Letency of evoked potentials (EPs) recorded in the anesthetized cat's magnocellular part of red nucleus varied from 3.5 to 4.5 msec on binuaural and contralateral stimulations. In ipsilateral stimulation, latency of EPs varied from 6 to 10.5 msec. EPs of the parvocellular part of the red nucleus were of two types: EP of the first type had latency of 4-5 msec, of the second type -6.5-10.5 msec on binaural and contralateral stimulations. In ipsilateral stimulation EP of the first type occurred with latency of 6-9 msec, those of the second -8.5-14 msec. Both latency and amplitude of the responses depended on intensity of the auditory stimulation. Possible ways of transmission of auditory information to red nucleus are discussed.

Animals↗
PubMed1978

[Responses of cat cerebellar cortex neurons to stimulation of the caudate nucleus, globus pallidus and substantia nigra].

Impulsive responses (IR) of the Purkinje cells (PC) and other units of the cerebellar cortex in the paramedian lobules, lobulus simplex and tuber vermis were evoked by stimulation of nucleus caudatus (NC) in cats under chloraloze-nembutal narcosis. The phasic IR as simple discharges (due to mossy fibre activation) were exhibited mainly with a latency of 5-12 and 14-20 ms; a latency of the compound responses ) due to climbing fibre PC activation) was equal to 5-6, 9-22 ms and more. There were differences in rhythmic reproduction of the responses depending on their latency. The recruitment responses were found during a 4-6/s NC stimulation. There was an inhibitory pause as an obligatory component of the tonic neuronal responses. Reactions of the same types (phasic and tonic) as in the case of the NC stimulation, but differing in unit's quantitative distribution according to the latency appeared in the globus pallidus (GP) stimulation. The minimal latency was 4 ms. Recruitment was observed as well. The substantia nigra (SN) stimulation evoked PC responses, activated by the climbing fibres with a stable latency (8.5 +/- 0.3 ms). SN, GP, n. inferior olive as well as thalamic nuclei are considered to play a definite role in realizing caudate-cerebellar connections, both oligosynaptic and polysynaptic.

Animals↗
PubMed1977

[Influence of destruction of the lateral reticular nucleus and nuclei of the inferior olive in cats on electrical responses of the cerebellar cortex evoked by stimulation of the vagus nerve].

The role of the lateral reticular nucleus and inferior olive in production of the cerebellar cortex evoked potentials to stimulation of n. vagus was studied on 28 cats under chloralose-nembutal narcosis. After electrolytical destruction of the lateral reticular nucleus prolongation of the latency and a decrease in the evoked potential amplitude were observed, especially ipsilaterally. After bilateral destruction the potentials could be depressed completely. A conclusion is made that the lateral reticular nucleus provides a relay to to the cerebellar cortex of interoceptive vagal impulses. Appearance of predominantly simple discharges of the Purkinje cells responses to vagal stimulation is considered as an additional evidence for such a role of the lateral reticular nucleus. After damaging the inferior olive the evoked potentials arose with unchanged latency but reduced in the amplitude. Significance of the inferior olive as an intensity regulatory for the interoceptive impulse flow to the cerebellum is discussed.

Animals↗
PubMedDate not supplied

[The organization of instrumental food-procuring movements in rats].

The roles of the lateral hypothalamus, basolateral nucleus of the amygdalar complex, the second field of the frontal cortex, and ventromedial thalamic nucleus in organization of the fast ballistic food-procuring movements were studied in albino rats. Sequences of uni- and bilateral destruction of the brain structures were assessed by photorecording. Movement-related neuronal activity in these structures was recorded in freely moving animals. A specific involvement of each of the above listed structures in organization of food-procuring movements was shown. The lateral hypothalamus seems to participate in initiation of the motor program and its efficient realization, the basolateral amygdala appears to produce activatory, training, and stabilizing effects. The second field of the motor cortex leads in movement acquisition (i.e., in memorizing) and decision making about triggering the program. The idea about the relay role of the thalamic motor nucleus is supplemented by understanding of its more complex integrative function.

Amygdala↗
PubMedDate not supplied

[Laterality of food handling movements in rats].

Lateralization of motor food skills has been investigated on 77 adult white rats. The predominance for the left anterior extremity while carrying out food was found in 53.5% of rats, the right extremity--in 36.4% of rats. 10.3% of rats belonged to ambidexters. Prevalence of using left extremity was peculiar to the females as against the male ones. Three generations of left-handed rats obtained by crossing have been followed. Rats making use of the left extremity to take out food predominated in the second and third generates.

Animals↗