[Role of endogenous neurohumoral factors in mechanisms of the pathogenesis and compensation of unilateral movement disorders after serial removal of the motor neocortex]. / Rol' éndogennykh neirogumoral'nykh faktorov v mekhanizmakh patogeneza i kompensatsii odnostoronnikh dvigatel'nykh rasstroistv posle seriinykh udalenii motornogo neokorteksa.

The role of neurohumoral factors in the mechanisms of restoring the lost motor functions after two successive unilateral removals of the neocortex motor region, was studied. The dynamics of the restoring correlated with the posture asymmetry factor (PAF) activity in the CSF. PAF activity was reduced during the restoring by an inactivation factor (FI). Periods of restoration after the 2nd extirpation and inactivation of PAF were shorter than after the 1st one. The existence of the FI before the 2nd extirpation may account for this phenomenon.

[Systems mechanisms of internal inhibition]. / Sistemnye mekhanizmy vnutrennego tormozheniia.

The state of internal inhibition is analysed which is considered as a multifactor systemically organized process. On model of combined presentation of positive and inhibitory stimuli in experiments on white rats and dogs, a dependence is established of the efficiency of reinforcement cancellation factor on motivation intensity. Condition of negative emotion--frustration, "difficult state"-is a necessary link in the process of internal inhibition formation, since it is responsible for selection of non-reinforcement for storage in the long-term memory. Conclusion is made that active inhibition of goal-directed behaviour is mediated by actualization of memory trace, "engram of non-reinforcement" by negative conditioned stimulus.

[Change in the functional significance of structures of the cat brain as a result of reorganization of its activity]. / Izmenenie funktsional'noi znachimosti struktur golovnogo mozga koshek kak rezul'tat reorganizatsii ego deiatel'nosti.

A study was carried out on 8 adult cats of functional role of the frontal, parietal and occipital parts of the neocortex, and also of the dorsal hippocampus, mediodorsal thalamic nucleus and caudate nucleus head, in realization of a delayed spatial choice (DSCh) before and after compensatory reorganizations of the brain activity caused by multiple electrical stimulation of the frontal part of the cerebral cortex. Compensatory reorganization led to a change of functional significance of these structures. While before this change the frontal cortex, hippocampus and mediodorsal thalamic nucleus were critically necessary brain areas for the realization of the DSCh, after it parietal and occipital cortical areas acquired such significance. The obtained data are discussed proceeding from the principle of the integrity in the brain activity.

[Reactivity of neurons of the orbito-frontal cortex of the cat during exposure to the scent or sight of food]. / Reaktivnost' neironov orbitofrontal'noi kory koshek na fone deistviia zapakha ili vida pishchi.

Reactivity of neurones in orbitofrontal cortex of the cat to the action of light or sound was studied in consecutive stages of alimentary behaviour conditioned by the smell and then the sight of food. Changes were found of the character of neuronal reactions to the light and sound stimuli at the change of smell to the sight of food. A conclusion is drown, that polysensory properties of the neurones of the orbitofrontal cortex provide integral organization of brain sensory function at separate stages of alimentary behaviour.

[Probability analysis of elements of rat behavior after sudden and signalled interruption of food reinforcement]. / Veroiatnostnyi analiz élementov povedeniia krys pri vnezapnoi i signaliziruemoi otmene pishchevogo podkrepleniia.

Probability analysis was carried out of the appearance of single elements of rats behaviour in the process of extinction of a conditioned alimentary motor reflex. The dynamics of effector behavioural components at a sudden cessation of reinforcement (usual schedule of extinction) was compared with cessation of reinforcement signalled by a previously differentiated signal and with reinforcement cessation preceded by a stimulus initially unknown to the animal. If the reinforcement cessation is signalled by a previously differentiated (negative) stimulus, in response to its action the animals "loose the aim", what is revealed in a rapid complete reduction of all elements of the goal-directed alimentary behaviour. Obviously differentiation signal actualises the memory trace of "nonreinforcement" which was formed in the previous negative experience of the animal; this is revealed in accelerated inhibition of the alimentary motor reflex under extinction.

[Importance of traces of a preceding unreinforced stimulus to the formation of inhibitory conditioned reflexes in the rat]. / Znachenie sledov predshestvuiushchego nepodkrepliaemogo stimula dlia formirovaniia tormoznykh uslovnykh refleksov u krys.

The results of experiments with the inhibitory signal presented to rats after the positive one, showed the significance of the negative signal memory trace which interrupted alimentary behaviour and considerably accelerated its full extinction in response to the previously positive signal. Its significance is shown in experiments with amnesia produced by electroshock. According to the suggested concept negative conditioned reflexes are a result of formation of a temporary connection between memory traces of the negative conditioned signal and the non-reinforcement of this signal.

[Systems organization of cerebral processes in the cat during learning while undergoing electrical stimulation of the neocortex]. / Sistemnaia organizatsiia protsessov mozga koshki pri obuchenii na fone élektrostimuliatsii neokorteksa.

A delayed spatial choice (DSC) was elaborated in five cats during electrical stimulation (ES) of the frontal cortical parts with a frequency of 80 imp/s. Then the task fulfillment was tested following cessation of the electrostimulation or under the action of other current frequencies (35,3 and 120 imp/s). The number of erroneous choices increased in the absence of ES or during 3 imp/s ES of the frontal parts. The effects of frequencies of 35,80 and 120 imp/s did not differ. Three cats were trained to DSC without ES. The conditioned reflexes were tested during ES of the frontal cortical parts with current frequency of 3 and 80 imp/s. Statistically significant increase of the number of erroneous responses took place in both situations. The obtained data are discussed from the point of view of the integrative activity of the cerebral structures in DSC. Its disturbance during ES of the cortical zones and dissociation (discordance) after cancellation of stimulation during which the conditioned reflex had been elaborated, point to systemic organization of brain functioning in goal-directed forms of behaviour.

[Different behavioral acts induced naturally or by electric stimulation of the brain]. / O razlichnykh povedencheskikh aktov, vyzyvaemykh estestvennym putem i élektricheskoi stimuliatsiei mozga.

A comparison was made between the reinforcing properties of a purposive attack provoked by stimulation of the hypothalamus and those of natural behaviour based on a certain motivation and exteroceptive stimuli. A model of an experiment with two cats has been evolved which made it possible to study simultaneously their behaviour in response to one and the same indifferent stimulus, reinforced in one cat by stimulation of the hypothalamus, while for the other, the stimulus acted as a signal of the attack on the part of the stimulated cat. It was shown that conditioned reflexes were not elaborated on the basis of reinforcement of the indifferent stimulus with behavioral effects of the purposive attack, produced by stimulation of the hypothalamus. It is assumed that conditioned reproduction of the purposive attack is impossible due to the absence of natural motivation; hence behavioral acts imposed by stimulation of the brain are not fixed in the memory.

[Structural-functional reorganization of the brain after sequential removal of the regions of the motor cortex in cats and dogs]. / Strukturno-funktsional'naia perestroika mozga pri posledovatel'nykh udaleniiakh uchastkov motornykh zon kory polusharii u koshek i sobak.

It was shown in experiments on cats and dogs that the greater the mass of removed motor cortex on one side, the longer the time for restoring lost motor functions. Repeated ablations of the areas adjacent with the previously extirpated cortical zone after the restoration of motor functions, bring about the recurrence of the same disturbances. However the period of restoration after each repeated extirpation is perceptibly shorter. This means that repeated extirpations of cortical areas result in the activation of the mechanisms directed at the reorganization of the brain sensorimotor functions as a new integral system and providing for normalization of the motor functions.

[Stimulus recognition as a factor in establishing the effective properties of the signal]. / Opoznanie stimula kak faktor stanovleniia éffektivnykh svoistv signala.

An attempt was made to estimate the importance of preliminary perceptual learning of the recognition of indifferent stimulus for the formation of effective properties of the trigger signal of conditioned reflex functional system. The dynamics of the elaboration of instrumental conditioned reflexes was compared: 1) when an unfamiliar signal was introduced into the experimental environment (control experiments). 2) in case of introduction of a perceptually familiar signal, 3) after "erasing" of acquired perceptual experience by electroshock. The experiments revealed that a preliminary perceptual learning contributes to the formation of the effective properties of the trigger signal.

[Role of dominant motivation in producing the effects of electric stimulation of hypothalamo-limbic structures]. / Znachenie dominiruiushchei motivatsii v proiavlenii éffektov élektricheskoi stimuliatsii gipotalamo-limbicheskikh struktur.

The experiments were made on cats with electrodes chronically implanted in the hypothalamus and the amygdala. The effects of electrical stimulation of the points from which the food reactions were initially evoked, were transformed into an avoidance reaction, if stimulation was applied in surroundings where the animals had previously received pain stimuli. Defensive reactions to stimulation of the hypothalamus and amygdala changed to alimentary reactions if the same stimulation was presented to hungry cats in conditions of repetitive feeding. A conclusion has been drawn that the elements of the hypothalamo-limbic structures have plastic properties and may be involved in different forms of behaviour, depending on current motivation and learning.

[Spatial-temporal synchronization of cerebral biopotentials and the problem of the brain's activity as a whole]. / Prostranstvenno-vremennaia sinkhronizatsiia biopotentsialov golovnogo mozga i problema ego tselostnoi deiatel'nosti.

The author compares the results of his own investigations into the influence of instantaneous and multiple reversible (cold) inactivation of the neocortex on the manifestation and elaboration of conditioned reflexes in cats with dynamic characteristics of spatial-temporal synchronization of biopotentials in the cortex and subcortical formations at different stages of formation and manifestation of the conditioned reflex in animals, and in different functional states (emotions and mental stress) in humans, as presented in the studies by M.N. Livanov and coworkers. It has been stressed that different experimental approaches reveal the one principle of brain functioning, its integral involvement in any purposeful activity.

[Role of a change in the electric conductivity of an epileptiform focus in the spread of paroxysmal activity]. / Znachenie izmeneniia élektroprovodnosti épileptiformnogo ochaga v rasprostranenii paroksizmal'noi aktivnosti

In acute experiments on unanaesthetized cats a study was made of the influence of shunting a region of the cortex with a metal plate on its electrical activity and impedance. Shunting of a region of strychninization reduces the amplitude of paroxysmal oscillations in the focus and in remote regions of the cortex, reduces their frequency and produces a considerable lowering of the impedance both in the regions of the cortex between the active electrodes and between active and indifferent electrodes. Impedance of the strychninized cortex is lower than the total resistance of the intact neocortex; this testifies to the rise of conductivity in the area of strychninization, which is similar to application of a shunting plate. The data obtained corroborate the substantial role of the bioelectrical field in the development of electroencephalographic paroxysmal manifestations.

[The role of the temporal neocortex in the origin of convulsive activity]. / Znachenie visochnogo neokorteksa v proiskhozhdenii sudorozhnoi aktivnosti

Experiments on cats with cooling capsules implanted over different areas of the neocortex have shown that cooling of different intensity applied to the temporal neocortex may result in both stimulation and switching off effects. Cold stimulation (temperature dropping to 27-33 degrees C) manifested in generalized epileptiform brain electrical activity and paroxysmal states. The functional switching off the temporal area observed during its deeper cooling (20-21 degrees C) discontinues the paroxysmal state already developed and prevents the appearance of seizures, regrardless of the localization of the epileptogenic focus. The paroxysmal state weakens and ceases after repeated cooling of the temporal neocortex. The temporal neocortex, involved in the integrated activating brain system, plays a decisive role in the emergence of paroxysmal states.