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G P Udalova

Publications and source records attributed to G P Udalova.

At least 19 recordsLinked to original sources
PubMed2006

The role of motivation in the performance of conditioned reflex switching of a maze skill in response to substitution of food reward quality in ants of the species Myrmica rubra.

The characteristics of learning in ants - active Myrmica rubra foragers - were studied in a maze at different levels of colony carbohydrate food need with reinforcement consisting of carbohydrate (sugar syrup) or protein (pupae of Lasius niger ants). Measures of the maze skill during learning reinforced with syrup were somewhat worse than those during learning reinforced with pupae, especially in terms of time-based measures. Ants were able to modify the acquired conditioned reflex reaction when the quality of reinforcement changed. At high levels of food need (" hungry" colony), substitution of syrup with larvae and vice versa was followed by transformation of the previously formed skill; this occurred at both experimental periods (training and testing). At low levels of motivation ("sated colony"), the optimized maze habit formed with protein reinforcement was replaced in the test with carbohydrate reinforcement by a "stochastic," unoptimized behavior with a dominance of investigative activity. These experiments demonstrated that conditioned reflex switching can occur in higher social insects - ants - in which the different forms depend on the level of colony need for food and, respectively, on the level of social food-related motivation of forager ants. The special importance of using the switch activating the corresponding motivational system before changing the reinforcement food quality is emphasized.

Animals↗
PubMed1983

Hemisphere specialization, bilaterality, and sex dimorphism in noise resistance.

This study shows the existence of right-sided lateral specialization of hemisphere noise resistance control of visual discrimination in rats. As a rule, right hemisphere activity, to a greater degree than left hemisphere activity is conducive to the improvement of noise resistance, the left hemisphere sometimes making it worse. Indications have been obtained concerning the existence of sex dimorphism of noise immunity in rats' visual discrimination. It is possible that the intact and split brain are more noise resistant in males than in females and are characterized by a greater asymmetry. The role of bilateral mechanisms in noise resistance is described: after section of the corpus callosum, noise resistance may either improve or deteriorate. It has been found that interhemispheric asymmetry can be changed up to its inversion by means of one of the hemisphere's polarization.

Animals↗
PubMed1983

[Hemispheric asymmetry of the space-motion component of a food-conditioned motor reflex].

The preference of movement direction in the process of motor food conditioned reaction has been investigated in rats with intact brain and after unilateral cortical inactivation. It was shown that the degree of motorspatial preference diminished with the maturation of reaction. At the high level of differentiation the valid preference was shown only in 38% of animals investigated but it was absent in the rest of animals. After inactivation of right hemisphere cortex left-side preference occurred in the presence as well as in the absence of the original preference. Inactivation of the left hemisphere cortex is less significant; it influences the original preference of movement direction permanently affecting those animals which normally had evident preference. It is concluded that the right hemisphere cortex plays dominant part in both sensor and motorspatial components of motor food conditioned reaction. It is supposed that the definite relationship exists between the degree of preference of movement direction and the functional asymmetry of cerebral hemispheres.

Animals↗
PubMed1983

[Lateralization of hemispheric control over interference resistance].

Bilateral mechanisms, the hemisphere specifics and the sexual dimorphism of the visual system's resistance against hindrance were studied in conditioning and electrophysiological experiments in rats and cats. A right-sided specialization of the hemisphere control over visual recognition in noise and its resistance against hindrance was revealed in rats: activity of the right hemisphere aids to a greater extent to picking up of relevant signal out of noise than that of the left hemisphere. Role of bilateral mechanisms in the visual system's resistance against hindrance was described in cats and rats: after the callosotomy the picking up of relevant signals out of noise could either improve or get worse, depending on a number of conditions. The dominant mechanisms were shown to play a major part in formation of a certain level of the resistance. Both the intact and the split brain seems to be more resistant against hindrance and to have a greater asymmetry in males. The data obtained contribute to corroboration of presence of the brain lateral specialization in animals and are interpreted on the basis of the inductive-deductive hypothesis of the brain lateralization origin.

Animals↗
PubMed1981

[Layer-by-layer analysis of transcallosal responses in the cat sensomotor cortex].

Transcallosal responses to stimulation of the cortex at the depth of 0.5 mm had the least phase I and the greatest phase II as compared with their values at a deeper stimulation. The maximal phase II occurred at the 1 mm stimulation. At a fixed depth of stimulation the maximal amplitude of the phase I coincided with the depth of stimulation. At 1 and 2 mm stimulations, the second maximum of the responses occurred at the depth of 2 and 1 mm, resp. The data obtained suggest that the callosal connections are organized in a "layer--to--layer" way, and that there are some cross--connections between the layers III and V ("one layer--another layer").

Animals↗
PubMedDate not supplied

Behavioral plasticity of Myrmica rubra ants during learning in a multi-alternative symmetrical labyrinth.

The problem of behavioral plasticity in insects was studied with red ants, Myrmica rubra, by altering a habit developed in a multi-alternative labyrinth with care for offspring as motivation. In altering the habit, location of reinforcement was changed: in the first series, the brood was transferred from the target areas to relatively symmetrical areas of the transverse axis of the labyrinth; in the second, reinforcement was left on one area that had not been preferred during learning of the target area. In both situations, the ants displayed the ability to alter labyrinth habits. The first alteration was the more complex, and 62.5% of the ants were able to manage it while 87.5% managed the second. Such indices as the first correct solution, the average number of movements in the cycle, and total number of correct cycles were also poorer for the first alteration. Development of a new motor habit was accompanied by a change (intensification) of the initial spatial-motor asymmetry. Individual variability in ant behavior were more evident in alterations. The animals not able to manage alterations exhibited definite preneurotic traits. It is suggested that ants have high plasticity and ability to successfully modify their behavior to correspond to change in the experimental situation.

Animals↗
PubMedDate not supplied

Behavioral strategies in ants in changing conditions of food motivation.

Learning in ants was studied in a multiple choice symmetrical maze at different levels of social food motivation. Myrmica rubra scout ants were found to be able to change their behavioral strategy rapidly when families were suddenly changed from a low level of motivation to a high level and vice versa. In the "sated" state, there was clearly evident investigative activity, which led to high levels of variability and instability in the maze habit. In the "starved" state, there was a rapid minimization of movement trajectories, and most ants used only one dominant movement scheme. The initial level of food motivation determined how ants learned in the maze and their ability to change their behavioral strategy.

Animals↗
PubMedDate not supplied

The behavior of ants in a maze in response to a change from food motivation to protective motivation.

The ability of Myrmica rubra scout ants to modify the foraging habit, formed in a symmetrical multiple-choice maze, in the situation in which the reinforcement (syrup) was replaced with a brood of the same species was studied. When the "test" was performed at the same high level of food motivation of the family as applied during training, the ants were able successfully to transfer to another type of social behavior - transporting of the brood. When the high-level food motivation was replaced with a low-level motivation, some of the ants were unable to modify the habit. Preliminary utilization in these conditions of reinforcement as a switching factor addressing the motivational system for protective behavior promoted successful performance of the "test." Criteria allowing identification of different methods of modifying behavior during the switch from food motivation to protective motivation were developed. A total of 37.5% of the ants transferred the strategy formed during training: 40.6% showed gradual remodeling. while 21.9% of individuals immediately used the new strategy.

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