Vol 74, No 4 (2024)

The review analyzes neurophysiological correlates of the implicit component of cognitive bias in the processes of perception and decision-making. The review identifies the leading methodological pipeline for analysis of the implicit component of cognitive bias, and justifies its choice in terms of the objectives of this review. The method of recording event-related potentials (ERPs) was chosen as the main approach to determining neurophysiological indicators of implicit processes. The analysis of literature allowed us to identify ERP components reproduced in the works of different authors using different variants of experimental designs for studying implicit bias, which may indicate the presence of common neurophysiological mechanisms associated with implicit processes in cognitive bias. The possibility of using other approaches to the analysis of EEG data to obtain new information about the mechanisms of implicit components in cognitive bias is also discussed.

Tactile play and playful massage are a normal interaction between adults and children in many cultures. Experimental data show that activation of the C-tactile system during such playful touches contributes to children’s socialization and the establishment of psychoemotional bonds in the parent-child dyad. However, comprehensive studies of the effects of different types of touch on perception of tactile stimulation in children have not been conducted before. Twenty-three children participated in the present study: 10 in the preschool age group and 13 in the elementary school age group. Children in both groups received play massage containing different types of touch with simultaneous recording of electroencephalogram (EEG) and heart rate. EEG processing included determination of spectral power, alpha rhythm peak frequency and fractal dimension. Analysis of the results showed that the relaxing effect of the procedure was more pronounced in children of primary school age, which can be explained both by the greater maturity of the CNS and the greater need for tactile contact, which is not realized in the school environment.

The purpose of this study is to test the hypothesis that personality traits and stressful situations experienced in childhood could be associated with the level of serum cortisol. The sample included 121 healthy adult men of Yakut (Sakha) ethnicity aged 18 to 27 years. To assess personality traits, the TCI temperament and character questionnaire by R. Cloninger was used. Serum cortisol levels were assessed by enzyme-linked immunosorbent assay (ELISA). It was found that such a temperament trait as “reward dependence” is associated with higher level of cortisol in the blood (p = 0.04). Experienced stressful situations are associated with the character trait “self-transcendence” (p = 0.049) but do not significantly affect cortisol levels. In individuals with high levels of stress, significant correlations were found between the “novelty seeking” (r = 0.33) and “self-directedness” (r = 0.36) with serum cortisol levels, which may reflect the prolonged effect of stress on increasing the sensitivity of the adrenal cortex. The results indicate a possible connection between one of the human temperament traits “reward dependence” and higher levels of cortisol in the blood. A high level of experienced stress situations reduces scores on the character trait “self-transcendence.”

Recognizing one’s own face is important for self-identification and is considered an indicator of self-consciousness. Social anxiety is related to special attention to self. The aim was to investigate the oscillatory dynamics associated with self-recognition/non-self-recognition in morphed faces and the correlation with social anxiety in these processes. During EEG recordings with 128 electrodes, 48 volunteers (31 females) recognized themselves in morphed faces. During self-recognition, a greater increase in theta rhythm was revealed in the time interval from 800 to 1500 ms than in the non-self-recognition condition. Based on the data on the relationship of the theta rhythm with attention and memory, it could be assumed that the increase in theta rhythm may be related to memory and attention processes when perceiving details, mismatches, and misrepresentation of one’s own face. Social anxiety was positively related to the magnitude of theta rhythm during self-recognition, it could be related to the increased attention that socially anxious people focus on themselves and distortions of their own face.

The study of the role of social isolation in the pathogenesis of addictive behavior disorders is an important medical and biological problem. Of particular importance are the limitations of social experience in ontogenesis. This work makes an attempt to find a connection between social isolation in ontogenesis and impulsive-compulsive behavior, as an indicator of the premorbid background for gaming and other forms of behavioral addictions. The mechanisms of addictive behavior in rats reared in isolation (IS) were investigated by analyzing the extracellular release of dopamine in response to stimulation of the positive reinforcing zone. Before the experiments, male rats were kept in individual cages from the 21st day of birth to the 90th day. To study elements of addictive behavior, a variant of the Iowa Gambling Task in a 3-arm maze and a method of developing compulsive overeating using intermittent consumption of high-calorie foods were used. To study compulsive behavior, a marble test was used against the background of withdrawal from a high-calorie diet. Surgeries were performed to implant electrodes into the ventral tegmental area (VTA) and the nucleus accumbens in rats exhibiting elements of addictive behavior in the 3-arm maze. These animals were then trained to respond to VTA self-stimulation. Dopamine release was recorded telemetrically in freely moving rats in response to electrical stimulation of the VTA self-stimulation zone. Fast scan cyclic voltammetry was used to determine changes in dopamine levels in the extracellular environment of the nucleus accumbens. IS entered less into the arm with a high degree of probability but with a low reward, and entered more in the arm with a low degree of probability, but with a high reward, which is associated with the appearance of impulsivity in behavior. In the model of compulsive overeating, the number of approaches to the feeder in IS increased, and against the background of withdrawal of high-calorie food, IS were more active in the marble test. In IS exhibiting elements of addictive behavior in the 3-arm maze, the content of extracellular dopamine in response to electrical stimulation of the VTA self-stimulation zones did not reveal any differences compared to the control group of rats with addictive behavior in the maze. At the same time, IS exhibiting elements of addictive behavior in the maze showed a more pronounced dopamine response to a complex stimulus: a conditioned signal used during maze learning light + VTA stimulation. Thus, rearing in the IS causes an increase in dopamine release in the nucleus accumbens in response to stimulation of the positive reinforcement area associated with addictive behaviors: impulsivity and compulsivity. A conclusion is drawn about the prospects of studying the extracellular release of dopamine and assesses addictive behavior disorders caused by limited social contacts in ontogenesis.

The intrinsic-signal optical imaging is widely used in experimental, theoretical and applied research of the mammal’s brain neocortex functional anatomy. However, a neural activity signal is hidden by the background activity, the amplitude of which is an order of magnitude larger than the mapping signal amplitude. Most of such background activity represents spontaneous oscillations in 0.01–0.15 Hz frequency range related to vasomotor oscillations. In this paper, we point out that such oscillations change their power and phase during the response time course. The most dramatic influence is intrinsic for 0.05–0.15 Hz oscillations. The power of vasomotor oscillations declines more quickly than the stability features of their phase characteristics. Departing from these data, we suggested approaches for minimization of role of vasomotor oscillations in functional maps resulting from intrinsic-signal optical imaging.