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Behavioral experiments were run to study the capacities of Macaca mulatta monkeys to perform cognitive tests of different levels of difficulty presented on a computer touch screen. The task consisted of recognizing the dominant orientation in textures with different levels of ordering. Rates of learning were analyzed, along with the proportions of correct responses and task solution times in relation to task difficulty. The extent of exploratory activity was evaluated in parallel, in terms of reactions to unfamiliar objects (the “reaction to a novel object” test). The proportion of correct responses increased with increases in the ordering of the test images and was comparable with results obtained previously in humans in similar experimental conditions. In monkeys, the index of exploratory activity correlated with the rate of learning and was lower in those animals inclined to distraction of attention, i.e., with longer response times. The results obtained in monkeys allow the neural processes occurring in the human brain on recognition of objects to be modeled, from the encoding of the physical properties of images to decision-taking. The interaction between the level of exploratory activity and the rate of learning allows the “reaction to a novel object” test to be used for selecting potential individuals for participation in behavioral experiments, significantly reducing the time spent on training the monkeys to new tasks.

Behavioral experiments were performed in which rhesus macaques were trained to interact with a computer using a touchscreen. Stimuli consisted of semitone images of Gabor elements with low spatial frequency with different contrast levels. The monkeys’ task was to touch the screen with the paw at the site at which the target stimulus appeared, which was followed by automatic delivery of a food or drink (juice) reward. Contrast was gradually decreased when correct responses were obtained. A two-way forced choice paradigm was used to measure the threshold contrast at which the monkeys could detect the appearance of low-frequency images. Decreases in the spatial frequency of stimuli were accompanied by decreases in contrast sensitivity, while reaction times increased. These data widen our understanding of primate activity in a virtual environment and make it possible to model and study a variety of human diseases.

In behavioral experiments rhesus macaque monkeys were trained to interact with the computer using a tactile display. We used grayscale Gabor patches of low spatial frequency as stimuli. Monkeys' task was to touch the screen with his hand in the area of the target stimulus, followed by automatic food or juice reinforcement. After two successive correct answers, stimulus contrast gradually decreased. Using a two-alternative forced choice method the contrast threshold was measured within which monkeys can detect the appearance of low-frequency images. It was shown that the contrast sensitivity decreased with the decrease of stimulus spatial frequency, while the reaction time increased. The findings extend our knowledge of the primates' activity in the virtual environment and open new possibilities for modeling and studying various human diseases.

At the present time, it is considered that the phenomenon of particle binding on the surface of the fuel elements directly leads to the formation of the structures of constant density. Here, the particle binding stage is visualized as the crystallization of the dissolved substance (form) and dehydration of the dispersed particles (d.p.) on the surface [I]. The following observations (that are useful for ensuring reliable operation of the fuel elements) reflect this concept: safe operation of the fuel elements is determined only by the effect of the total thickness of the deposit (precipitate) layer; the coefficient of thermal conductivity of the deposits remains constant.