The mapping of brain biopotentials during the solving of a verbal task]

Reverse averaging of cortical potentials from the moment of the motor response followed the verbal task solving (anagram riddle) revealed some brain potentials correlations with the process of a decision making. In the case of task solving the negative frontal wave with the latency 900-400 ms from the motor response was recorded. Intracortical interaction mapping of this potential showed the regular patterns of cortical functional connections in different frequency ranges (alpha, beta). Successful solving of the task was characterized with predominant interaction foci topography in the frontal and left-temporal cortical areas in alpha band and parietal zones in beta. The absence of the task solution was characterized with the parieto-occipital interaction foci in alpha band and their frontal localization in beta.     

The reflection of emotional tension in the spatial synchronization of the biopotentials in the human brain

In organization of spatial synchronization of bioelectrical activity of the cerebral cortex emotions can play both the role of intensifier and disorganizer of this process. Emotions raise the level of spatial synchronization in situation of active work and may decrease initial background values of synchronization if they organize passive-defensive state.     

The intercentral relations of the biopotentials in the rabbit brain during the creation of a blinking dominant]

On rabbits in chronic experiment intercentral relations were studied of biopotentials of the sensorimotor cortical zone (blinking presentation in the cortex), VPM of the thalamus and motor nucleus of the oculomotor nerve at formation of blinking dominant created by serial stimulation of one eye by air jet. By the method of spectral-correlation analysis an increase was revealed of spectrum power and increase of COG of the potentials in delta-range in the structures connected with blinking function of the stimulated eye. At transition of the dominant focus to the inhibitory state and activation of the symmetrical centre of the other eye, in centers constellation of this induced focus a reconstruction of the electrical processes took place typical for the dominant.     

Spatial synchronization of rabbit brain biopotentials upon repeated electrical stimulation of the cortex]

A study was made on 23 rabbits of the degree of spatial synchronization in response to repeated electrical stimulations of one or simultaneously two cortical areas: the sensorimotor or visual, or simultaneously the sensorimotor and visual, or sensorimotor and precentral respectively. Enhancement of the synchronization induced by the stimulation, globally spread over the entire cortex and was followed by its decrease. However, in the two directly stimulated areas of the cortex, the similarity of bioelectrical oscillations persisted for a long time, which testifies to the establishment of selective relations between them.     

Motivation effect on power changes in the brain biopotentials in the figurative and verbal creativity tasks

Effect of extrinsic motivation stimulating the most original problem solving during verbal and figurative divergent thinking was studied by EEG mapping. The righthanded university students (27 males and 26 females) participated in the experiments. An instruction "to create the most original solution" as compared to condition with an instruction "to create any solution" induced an increase in the baseline power of the alpha 1 and alpha 2 rhythms most pronounced in the posterior cortex. Task-related desynchronization of the alpha rhythms was higher but the beta-2 synchronization was lower after the former than after the latter instruction. Differences in the asymmetry of the alpha 1 and alpha 2 rhythms in the parietal and temporal regions of hemispheres suggested the right hemisphere dominance in intrinsic alertness and evoked activation related to divergent thinking. The findings were common and gender-independent in both figurative and verbal tasks suggesting a generalized influence of extrinsic motivation on creative activity.     

Thermoencephaloscopy of brain responses to emotionally significant visual stimuli in depressive patients

The thermoencephaloscopic study of patients with reactive depression during exposure to emotionally significant visual stimuli detected a functional change in the state of the frontal associative area of the right hemisphere and the parietal associative area of the left hemisphere and the activation of the left temporal area, closely related to the limbic system. The data obtained may be used for the elaboration of new methods of diagnosis and therapy of reactive depressions.     

Some features of spatiotemporal organization of brain biopotentials in persons with different levels of anxiety and other personality traits

Anxiety and other personality traits were scored in 55 practically healthy subjects with the aid of 16-PF Cattell questionnaire. EEG was analysed by the mapping method after N.E. Sviderskaya. It was shown that two groups with equally high anxiety scores had different spatiotemporal organizations of brain biopotentials. The most "unfavorable" EEG characteristics were found in the group of "anxious conformists": poorly pronounced alpha rhythm with a low level of coherence in the alpha band was concomitant with the theta and beta rhythms with high levels of coherence and power density.     

Analysis of probabilistic characteristics of brain biopotentials in healthy humans using electronic computer technology]

Results are given of determination by means of a Minsk-22 electronic computer of the probabilistic characteristics and correlation coefficients for some parameters of the background EEG (frontal-occipital records) in a group of healthy subjects. The parameters studied (the number and amplitude of alpha- and other waves) are subject to the normal law of distribution of random values. A probabilistic model of background EEG has been plotted. Correlations between the factors of the statistic model of background EEG have been studied. The results presented in the paper may prove useful in studying the EEG characteristics and the functional state of the brain.     

Changes in the fast uterine muscle biopotentials in rabbits with chronic hypoxia

Changes of the high-frequency electrical activity in the myometrium after a separate and simultaneous ligation the uterine and ovarian vessels were studied in chronic experiments (137 experiments on 18 non-pregnant rabbits which had already had pregnancies in the past). The highest and most prolonged (up to 45 days) inhibition of the amplitude and frequency of rapid (peak) potentials of the myometrium follows a simultaneous ligation of the uterine and ovarian arteries and veins. The amplitude and frequency of biopotentials is gradually restored with the compensation of blood circulation by the collateral blood channels.