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The organization of distributed amygdalo-hypothalamic and local amygdalar and hypothalamic neural networks was studied in three cats, trained to perform a food-related operant conditioned reflex to light by the "active choice" of reinforcement quality method; pressing the pedal with a short latent period provided the cats with a bread/meat mixture, while pressing with a long latent period yielded meat. Animals showed sharp differences in their individual abilities to choose one or the other reinforcement. Two cats preferred long-latency pedal-pressing to obtain meat, and were considered to be "self-controlled," while the third cat, which preferred short-latency pedal-pressing to obtain the less valuable reinforcement (the bread/meat mixture) was described as "impulsive." Chronically implanted semimicroelectrodes were used to record multineuron activity in the basolateral nucleus of the amygdala and the lateral nucleus of the hypothalamus. Interactions between the discharge trains of neighboring and distant neurons were assessed by cross-correlation analysis. Interneuron functional connections were found to predominate significantly in the local neural networks of the basolateral amygdala and distributed amygdalar-hypothalamic networks in the "impulsive" animal as compared with the "self-controlled" animals, suggesting a role for these types of connection in forming the individual characteristics of higher nervous activity. The identical incidences of interneuron interactions in the lateral nucleus of the hypothalamus in cats with different individual preferences suggest that local networks in this formation are not involved in analyzing reinforcement quality.

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The organization of interneuronal cortical connections in intertrial periods was studied in 4 cats trained to perform the delayed appetitive instrumental response to a visual conditioned stimulus (CS). Crosscorrelationl analysis revealed changes in intra- and intercortical neuronal networks of the visual and motor cortical projection areas. Depending on the form of behavior in the intertrial period, i.e., the presence or absence of the acquired instrumental response, the functional connections of either informational (time delays of less than 30 ms) or motivational (time delays in the range of 60-100 ms) character dominated between the neurons of the motor and visual cortical areas.

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The organization of interneuronal cortical connections was studied in experiments on cats with the development of delayed alimentary instrumental reflexes in response to light. The dynamics of the intra- and interstructural neuronal network at the level of the cortical projection (visual and motor) zones of the cat brain in three forms of behavior was revealed through a cross correlation analysis: the realization of the CR, in the intersignal period with the presence and absence of instrumental movements. The predominance of "informational" or "motivational" neuronal connections was observed depending upon the forms of the behavior.

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In experiments on seven cats instrumental delayed reflexes with different quality reinforcement were elaborated by method of "active choice", where the time of delay of the motor reaction served as a signal of quality of the reinforcement. Five cats used a strategy with long delay high-quality reinforcement (meat), and two cats preferred short delay and low-quality reinforcement (bread-meat mixture). In special experiments with the change of alimentary motivation (24-hour alimentary deprivation and saturation of animals) it was established that the level of alimentary motivation within the studied limits did not change the strategy of behaviour preferred by the given animal. Individually varying ability to choice of reaction determining more valuable reinforcement it is possible to consider as an experimental analogue of the mechanisms of will. The question is discussed about the role of typological properties of cats in choice of behaviour strategy.

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Multiunit activity was chronically recorded in auditory, visual and motor cortex during classical conditioning and extinction. A statistical method for cross-correlation analysis of interneuronal relations was used. Plastic changes in cortical integrative function had spatial features and depended upon types of conditioning. Results suggest the spatial features in cortical cell integration in the trained-brain consisting of 3 categories of neuronal system organizations: microset, local and inter-regional. The first two are localized in a cortical projection region, whereas the third occupies cortical regions activated during conditioning. An evaluation of systemic activity in cortical neurons suggests specific organizations of cortical integrative functions in learning.

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Milk conditioned reflexes to low frequency electrostimulation of optic tracts was examined in four cats. Multineuronal activity from visual and sensorimotor cortical regions was recorded under conditions of chronic implantation. Intra- and interanalyzer interneuronal connections were statistically analyzed by constructing crosscorrelograms. The comparison of the results of interneuronal interaction in untrained and trained animals showed an increase of one-way and two-way connections both of intra- and interanalyzer types. Neurons characterized by intermediate amplitude spike, more than other neurons, changed their network properties and were enriched by incoming and outgoing connections in both visual and sensorimotor cortex of the trained animals. An increase in the total number of interneuronal connections after acquisition was due to an increase of connections from the sensorimotor to the visual analyzer.

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