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A Ia Kaplan

Publications and source records attributed to A Ia Kaplan.

11 recordsLinked to original sources
PubMed1992

[The cardiosynchronous phenomena of the work of the brain: the psychophysiological aspects].

The review is devoted to the heartbeat-related components of EEG and to the heartbeat-related oscillation of performance measures and the cortical evoked potentials. The studies of these phenomena are carried out within the Laceys' hypothesis elaboration as well as in the field of the exploration of visceral self-perception. The data obtained in these studies indicate that there are elements of the time-locking with heart rate, probably unrelated to cardiovascular regulation, in functioning of the highest brain structures. The problems in the interpretation of some of heartbeat-related phenomena of brain functioning and their possible participation in the mechanisms of the psychophysiological interaction are discussed.

Alpha Rhythm↗
PubMed1989

[Alternative animal behavior: a model and its statistical characteristics].

The rats' alternative behaviour in T-maze at simultaneous two-sided food refreshment in 13 trials a day during 6 days has been studied. It has been found that in the first testing days the indexes of alternative behaviour of animals correspond to the characteristics of the random alternation. However, on the 5-6th day of testing in the overwhelming majority of rats the true deviation of alternation index above or below than the theoretical values has been revealed. A question on the existence of two strategies of cognitive behaviour alteration and perseveration in rat population is under discussion.

Animals↗
PubMed1988

[Rhythmic activity of the olfactory bulb of the carp under nembutal anesthesia].

The effect of nembutal intraperitoneal injections upon the induced waves and orthodromic potentials of the olfactory bulb (OB) induced by odor stimulation and paired electric stimuli of the olfactory nerve was examined in immobilized by diplacine carp (cyprinus carpio L.). The nembutal anesthesia resulted in a gradual decrease in frequency of induced waves tested by orthodromic response and amplitude of spontaneous electric activity ob OB. The changes found under nembutal anesthesia in evoked electric activity of OB were also observed in chronic and acute intersection of the olfactory tracts.

Alanine↗
PubMed1987

[A simple dispenser for liquid olfactometry].

A simple mechanical device for the dosage delivery of the chemical substance solutions to the animal chemoreceptors is suggested. This device is making chemical stimuli with abrupt fronts by means of stream switching of the control and test solutions.

Animals↗
PubMed1976

[Reticular inhibition of evoked potentials of the ventro-basal thalamus and somatosensory cortex of the rat brain].

In rats immobilized with d-tubocurarine conditioning electrical stimulation (100/s, 300 ms) of the central grey matter, reticular formation of the midbrain and medulla depressed focal potentials in thalamic ventro-basal complex and somatosensory cortex evoked by electrical stimulation of the forelimb or medial meniscus. The average threshold current for conditioning stimulation of these structures was 70, 100 and 120 muA. A comparison of intensity and duration of evoked potentials depression (for two-fold threshold stimulation of the brain stem) is failed to detect any difference between the stimulated structures: immediately after conditioning stimulation the amplitude of the cortical evoked potentials and post-synaptic components of the evoked potentials in the ventro-basal complex were 50-60% less than control amplitude (p less than 0.01) the depression persisting for 0.5-1 s. The presynaptic component of the thalamic evoked potentials was depressed only after three five-fold threshold conditioning stimulation. The brain stem stimulation did not cause any facilitatory effect on focal potentials evoked by maximal and submaximal stimulation of the forelimb or medial lemniscus.

Animals↗
PubMedDate not supplied

[Dynamic characteristics of element-by-element reproduction of visual matrix images: phenomenology and pharmaco-testing].

An outfit "Mnemotest" was employed to examine some regularities of the operative memory of man. The dynamic characteristics are provided of reproduction-storage of the elements of visual matrix images: the curves of "fading" and the "reproduction tempo". It has been shown that oral administration in therapeutic doses of the psychostimulant sydnocarb optimizes the mnemonic processes. Under different conditions the drug either increases the "reproduction tempo" or minimizes the rate of the "fading" of the mnemonic trace.

Humans↗
PubMedDate not supplied

[Rhythmic activity of the endbrain in the carp evoked by adequate visual stimulation].

In acute experiments on immobilized carps, under dark adaptation conditions, studies have been made on the electrical activity of the telencephalon and midbrain tectum. It was found that in the latter photostimulation evokes local rhythmic activity which includes fast (30-50 Hz) phasic (200-300 ms) and slow (8-14 Hz) tonic (up to 3-4 s) components. High rhythm of this activity may be observed only in "healthy" preparations, coinciding with on-rhythm in the midbrain tectum. Low rhythm does not depend on the presence of rhythmic activity in the tectum. Various aspects of the development of the thalamo-telencephalic system in vertebrates are discussed.

Alanine↗