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The influence of spatial imprinting on cognitive activity of adult mice F1 from DBA/2J C57BL/6J in a transformable multialternative maze has been studied. A control mice initially learned in a maze with "direct" and "bypass" pathway between feeders. They successfully formed a food-getting habit after 9-10 sessions using mainly direct pathway, so the final route decision was consistent with the principle of least action. Experimental mice previously placed into reduced maze with only "bypass" pathway between feeders for 1-2 trials (1-3 min), and turn up in the complete maze immediately after that. Experimental mice could not organize a food-getting behavior according a task conditions since attempted to include in final decision both "direct" and "bypass" pathways, united in a single ring-like construction. They demonstrated situational behavior running from one feeder to another one, despite of fact that therein had no feed. So it opposed the realization of least action principle, becoming a source of psycho-emotional stress. The results showed that spatial information perceiving in the first few minutes of exploring the experimental environment can manifest itself as the acquired preference and come in conflict with an instinctive one. Cognitive dissonance predetermined the direction of the cognitive process.

The effects of repeated opilong injections in a dose of 50 microg/kg/day on subsequent learning of Wistar rats have been studied. The substance caused significant anxiolytic and analgesic effects, as the majority of animals could be learned (90% against 40% in control group) despite of painful stimulus preceding to education. Opilong in a small dose displaced a relation of excitatory-inhibit processes to significant prevalence of excitation although the substance was already absent in an organism for a long time. Raised peripheral sensitivity in all rats, provoked by opilong, correlated with CNS hyper excitability, expressed in stressful, neurotic psychoemotional reactions and in the form of active avoidance. The biochemical blood analysis in opilong-induced rats demonstrated the attributes of prethrombosis in the form of fibrinolysis depression and hypercoagulation. A view is expressed, that the neuromediator brain systems can be the basic point of opilong action, that are responsible for the excitatory-inhibit conditions of CNS functioning referred on maintenance of conditioned field stability.

Study of spatial learning in adult BALB/c mice revealed that a short exposition to the environment (from 3 to 8 minutes) could be enough for spatial information to be fixed in the long-term memory, and affected subsequent learning process in the new environment. Control group, learning in the same maze, followed the "shortest path" principle during formation of the optimal food-obtaining habit. Experimental animals, learning in a slightly changed environment, were unable to apply this rule due to persistent coupling of the new spatial information with the old memory traces which led to constant errors. The obtained effect was observed during the whole learning period and depended neither on frequency nor on interval of repetition during the initial information acquisition. The obtained data testify that memorizing in adult state share the properties with the imprinting process inherent in the early ontogeny. The memory fixation on all development stages seems to be based on a universal mechanism.

Effects of repeated piracetam (PIR) injections in a dose of 40 and 250 mg/kg/day on the learning in Water rats were studied. It has been found that character of the effects depends on typological features of the animals. Rats with strong predominance of excitation (choleric type) showed low sensitivity to PIR. Small dose of PIR provoked clear negative effect in rats with relative balance of the basic nervous processes: excitation and inhibition (sanguine and phlegmatic types). Despite of expressed activation of associative process, it complicated integrative activity. Small dose of PIR showed anxiolytic and psycho-stimulant actions only in initially unlearned rats characterized by high level of fear. Large dose of PIR had negative influence on the learning process in all animals, irrespective of typological features. Thus, the results of this study allow to suppose that the individual sensitivity of an animal to action of a pharmacological medication is caused by morpho-functional and neurochemical intraspecific heterogeneity.

The effects of 5 injections of salt solution and unfractionary heparin in dose 0.36 microgram/kg (Serva, Germany 10 kDa, activity 180 U/mg) have been studied in Wistar rats. It was found that two injections of salt solution were enough to form a stable defensive state in all rats which was manifested as an expectation of pain in tail-flick testing. The defensive motivation provoked by the injections negatively influenced the learning process as saline-induced rats refused to solve a food-getting task in a problem situation. Explorative and locomotor activities were depressed in these rats and were accompanied by numerous stressful and neurotic-like manifestations. Unlike saline-rats, practically all heparinized-rats instead of 45% of intact rats were able to solve a cognitive task despite the injections. Anxiety was decreased, but sensitivity to different external factors was increased in the heparin-induced rats. Formed habit in these rats was characterized by a high organization and stability. However, the majority heparin effects in tail-flick test were discovered when comparing the heparin-induced rats with intact ones and were not observed in comparison with the saline-rats. It is suggested that the saline-control should be considered as specific control having defensive features which are necessary to take into account in interpretation of effects of other pharmacological preparations.

The study aimed at revealing psycho-emotional manifestations of Wistar rats in a problem situation when they had to solve a food-getting task in a multi-alternative maze. Bilateral lesion of dorsal hippocampus did not affect the learning process while the pattern of psycho-emotional manifestations changed in all the animals irrespective of their individual properties. The pverall effect was manifested in flatness of psycho-emotional responses as a result of reduction of extreme forms of both passive and active stress responses. Individual effects depended on the behavioural phenotype. Hippocampus lesion in initially excitable rats (10%) resulted in reduction of active stress responses (act/pass = 0.35/0.5 instead of 1.0/0.4 in control). Hippocampus lesion in initially inhibited rats (30%) did not affect the basic pattern of psycho-emotional responses, while in the rats with initially depressed cognitive activity (60%) it resulted in decreasing of passive and increasing of active stress responses (act/pass = 0.45/1/4 instead of 0.3/1.9). The findings suggest that hippocampus takes part in the psycho-emotional responses while the individual psycho-emotional pattern is determined by the morpho-functional features responsible for organisation of a psycho-emotional condition.