Biomedical subjects

M L Pigareva

Publications and source records attributed to M L Pigareva.

24 records · Page 2Linked to original sources

PubMedDate not supplied

[Avoidance reactions to a partner's pain stimulation in rats with local brain damage].

Avoidance reaction to pain stimulation of another individual was studied in white rats before and after lesion of the frontal, cingular, entorhinal cortex, septum and median gray matter. The avoidance reaction improved following destruction of the frontal cortex and deteriorated after lesion of the median gray matter. A conclusion has been drawn that the participation of various brain structures in the investigated reaction is closely connected with other functions of these structures. The results obtained contradict McLynn's (1970) suggestion of a rigid dependence of definite forms of zoosocial behaviour on certain brain formations.

Animals↗

PubMedDate not supplied

[Individual features of rat behavior and limbic structures of the brain].

Bilateral ablation of the frontal parts of the neocortex and the hippocampus enhances the rats' reactivity to artificial stimuli (light and sound), and at the same time diminishes their sensitivity to signals of defensive excitation in another individual. Simultaneous bilateral ablation of the frontal neocortex, the lateral and ventromedial hypothalamus enhances in equal measure the rat reactivity to light, sound and the partner's pain cry. Comparison of the results with facts previously obtained and with published data suggests that individual correlations of the "information system" (the frontal neocortex and the hippocampus) with the "motivational system" (the amygdala and hypothalamus) underlie the extra-introversy parameter. Correlation between the "frontal neocortex--hypothalamus" and "hippocampus--amygdala" systems is manifested on the neuroticism (emotionality) scale. Activity of the "hypothalamus--hippocampus" system is of great importance for the lability versus inertia factor. The different forms of disturbance of normal interaction of the above four brain structures are likely to determine the basic varieties of neuroses.

Acoustic Stimulation↗

PubMedDate not supplied

[Switching-over of homogeneous (alimentary) conditioned reflexes in rats following simultaneous lesions of the hippocampus and amygdala].

Conditioned switching-over of homogeneous (alimentary) conditioned reflexes was elaborated in intact rats and in rats with simultaneously lesioned hippocampus and amygdala; time of the day served as switching stimulus. The operated rats showed higher values of intersignal and conditioned motor activity and easier conditioned switching-over than intact animals. It is suggested that the lesion of the amygdala enhances the effect of accelerated elaboration of the switching-over observed in animals with lesioned hippocampus, due to the elimination of competing (non-alimentary) motivations.

Amygdala↗

PubMedDate not supplied

[The advanced display of behavioral reactions in sensory deprived rat pups].

Bilateral section of nervus medianus was made in Wistar rat pups on 13, 14, 15 or 16-th days of life. Developmental analysis of motor abilities, locomotor and exploration activities during 10-30 days of life revealed three groups of facts. 1. Partial deafferentation of forelimbs don't influence on some types of behavior. 2. Some motor abilities hindered in rat pups with section of nervus medianus. 3. Partial deafferentation of forelimb gives rise to the faster appearance of the new types of behavior. The developmental analysis allowed to suggest that faster appearance of certain behavior reactions after deafferentation of the forelimbs is a result of actualization of latent sensory inputs including in the organization of these types of behavior but it is not connected with changing of velocity of morphological maturation.

Aging↗

PubMedDate not supplied

[Changes in the galvanic skin reaction and speech parameters of 8- to 9-year-old children during play].

Changes of parameters of the speech signal (fundamental frequency, Ef, and evaluation of the frequency of the first formant, n(0)) were compared to the skin galvanic (SGR) reaction shifts in 8-9 years old children during playing computer games under different conditions: 1) playing using the child's own strategy; 2) that under the conditions of time deficits; 3) that with minimization of errors. In each playing situation a child had 3 trials. Parameter SGR-1 reflected SGR amplitude changes depending on a trial number, SGR-2 reflected those depending on the beginning, the middle, of the end of a battle with an enemy. At playing under the conditions of time deficits there was an increase of emotional stress and that of the number of negative emotional reactions of children being accompanied by worsening of playing activity parameters. Ef and SGR-2 were mostly expressed in comparison to other playing situations. The greatest changes of n(0) and SGR-1 were observed at playing with child's own strategy. Emotional stress in the latter situation was minimal, number of positive emotional reactions was comparable to that in the third playing situation, and negative emotional reactions were absent. The data obtained point to the structural change of motivation at complicating the situation (at playing with time deficits).

Acoustic Stimulation↗

PubMedDate not supplied

[Sensory information--an important factor in ontogeny].

Ontogenetic process reveals a row of consecutive stages characterized by the gradual increase in complexity and by the changing specificity of sensory mechanisms basic for the adaptive behavior of the young. The study examines the mechanisms of interaction among different sensory systems during the formation of early behavioral patterns and analyzes why, at a certain stage of development, a particular sensory stimulus loses its efficacy in the organization of a given behavior and is substituted by another one, previously ineffective. A special attention is paid to formation of behavior based on sensory information within the limits of ontogenetically fixed developmental critical periods and to the role of the early sensory experience in learning in adult animals.

Aging↗