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BACKGROUND: The search for biological markers for the differential diagnosis of recurrent depression and bipolar depression is an important undertaking in modern psychiatry. Electroencephalography (EEG) is one of the promising tools in addressing this challenge. AIM: To identify differences in the quantitative characteristics of the electroencephalographic alpha band activity in patients with a depressive episode within the framework of recurrent depression and bipolar depression. METHODS: Two groups of patients (all women) were formed: one consisting of subjects with recurrent depressive disorder and one with subjects experiencing a current mild/moderate episode (30 patients), and subjects with bipolar affective disorder or a current episode of mild or moderate depression (30 patients). The groups did not receive pharmacotherapy and did not differ in their socio-demographic parameters or total score on the Hamilton depression scale. A baseline electroencephalogram was recorded, and the quantitative characteristics of the alpha band activity were analyzed, including the absolute spectral power, interhemispheric coherence, and EEG activation. RESULTS: The patients with recurrent depressive disorder demonstrated statistically significantly lower values of the average absolute spectral power of the alpha band (z=2.481; p=0.042), as well as less alpha attenuation from eyes closed to eyes open (z=2.573; p=0.035), as compared with the patients with bipolar affective disorder. CONCLUSION: The presented quantitative characteristics of alpha activity are confirmation that patients with affective disorders of different origins also display distinctive electrophysiological features which can become promising biomarkers and could help separate bipolar depression from the recurrent type.

Introduction. Congenital hyperinsulinism is a rare group of genetic disorders resulting in persistent hypoglycemia which can lead to delay of neurodevelopment.Aim. To assess psychomotor development and certain neurophysiological parameters of children treated for congenital hyperin-sulinism.Materials and methods. This prospective and retrospective cohort study included 73 infants with congenital hyperinsulinism admitted to the National Almazov Research Centre from 2017 to 2021. All subjects underwent standard clinical examination including physical and neurological assessment as well as 18F-DOPA PET/CT, genetic testing, electroencephalography. Developmental screening was performed using “Ages and Stages” questionnaire in 33 subjects. Possible risk factors for neurode-velopmental sequelae due to hypoglycemia were analyzed.Results and discussion. Normal neurodevelopment in general was observed in 23 subjects (69%), 10 patients had developmental delay. Focal form of CHI had the greatest modifying effect on positive neurodevelopmental outcome in general. Individual skills such as communication, fine and gross motor, problem solving in children with a focal form of CHI were significantly better than those with a nonfocal forms. Age of manifestation and verification of the disease, the minimum level of glycemia and the maximum level of glucose utilization did not significantly affect the formation of either individual skills (with the exception of gross motor skills) or psychomotor development in general. The indicators of gross motor skills in children with a lower level of glucose utilization turned out to be significantly better. Kaplan-Meier survival analysis showed that the alpha rhythm appearance was significantly earlier in patients with a focal form of CHI and with earlier verification of the diagnosis (

Introduction. This review article combines the theory of motivational intensity and the theory of mental effort with studies of oscillatory correlates of the performance of complex cognitive tasks. The phenomenon of effort has been a longstanding subject of research in fundamental psychology. Theories describing the cognitive mechanisms of mental effort have been developed in recent years. However, further research is needed to explain the mechanism of effort modulation during task performance. Theoretical justification. Mental effort can be defined as an active volitional process of mobilizing resources to maintain a particular behavior. The theory of motivational intensity, in conjunction with theories of mental effort, describes the cognitive and motivational factors that modulate the effort invested in the performance of a task. Interpreting the oscillatory correlates of individual cognitive processes in the context of effort theories may allow one to develop an understanding of the mechanism underlying the distribution and modulation of mental effort. The purpose of this paper is to review the existing experimental data on the modulation of task-related oscillations and compare the research results with the predictions of force theories. Results. The article reviews research on the power of oscillations as correlates of various controlled processes required by a cognitive task. The severity of the oscillatory effects associated with the performance of the task increases with the complication of the task and with increased motivation to perform. When performing particularly complex tasks, there are individual differences in indicators of brain activity, which, apparently, can only be explained through the motivational-emotional reaction of the subject to complexity. Discussion of the results. The effects found as a result of the literature review are consistent with the predictions of the theory of motivational intensity about the modulation of effort. However, to date, there is a lack of research to correlate oscillatory data with theories of effort and develop an understanding of the mechanism of force modulation under various task requirements. The article discusses possible studies on this topic and the features of the required experimental designs.

Objective: To compare the effectiveness of neurofeedback (NFB) at infra-low and alpha frequencies in the treatment of cognitive impairment in patients with early cerebral small vessel disease (cSVD)., Material and Methods: The study included 71 patients (average age 52.8±6.3 years, men 15%, women 85%) with early cSVD and 21 healthy volunteers (average age 53.2±4.8 years, men 29%, women 71%). All participants were assessed for clinical manifestations and cognitive functions, brain MRI, and EEG. cSVD patients were randomized by an envelope method with double-blind placebo control. Three groups of neurofeedback were formed: infra-low waves ( n =25), alpha waves ( n =22), simulated neurofeedback using EEG (placebo) ( n =24). Fifteen sessions of 30 minutes were conducted 2-5 times a week. The cognitive profile and EEG were assessed immediately and 6-8 weeks after completion of the neurofeedback course., Results: Patients with early cSVD had subjective (65%) and moderate (35%) cognitive impairment with predominant deviations in the components of executive brain functions (EBF). Neurofeedback using infra-low waves significantly improved EBF in the components of productivity, switching and inhibition, non-verbal delayed memory immediately after the course, maintaining the effect for at least 6-8 weeks, which was accompanied by an increase in the power (μB2) of the alpha rhythm in the occipital regions. Neurofeedback using alpha waves showed improvement in the Stroop test (interference index) in the delayed period., Conclusion: In patients with early cSVD and deterioration of EBF, it is preferable to conduct biofeedback neurotraining at infra-low frequencies to treat cognitive impairment and create a cognitive reserve. An increase in the power of the alpha rhythm in the occipital regions during the course can be considered a prognostic marker of its effectiveness.

Objective: To establish the relationships of functional changes of the brain of patients with schizophrenia with clinical manifestations of the disease and their constitutional and morphological features., Material and Methods: One hundred and eighteen patients with schizophrenia (64 men and 54 women), aged 33 [29; 40], years were examined. The following clinical and dynamic parameters were used: age of manifestation of the disease, duration of the disease, severity of clinical and psychopathological symptoms according to the PANSS. The anthropometric examination of patients was carried out according to V.V. Bunak's method in V.P. Chitetsov's modification for adult samples with calculation of Rees-Eysenk and Tanner indices. The EEG was recorded and analyzed in a state of calm, relaxed wakefulness with closed eyes with the calculation of the absolute spectral power for theta (4-7 Hz), alpha (8-13 Hz) and beta (14-30 Hz) rhythms., Results: Significant ( p <0.05) direct correlations between the age of the disease manifestation and the spectral power of the beta rhythm in the frontal leads (Fp1, Fp2, F3 and F4) were revealed. Inverse correlations ( p <0.05) were found between the duration of the disease in patients with schizophrenia and the spectral power of the alpha rhythm in the left temporal (T3) and right central leads (C4), the spectral power of the beta rhythm in the parietal-occipital (P3, P4, O1,O2) and temporal leads (T3, T4, T5), the spectral power of the theta rhythm in the left occipital (O1) and posterior temporal leads (T5). Significant inverse correlations were also found between the Tanner index and the spectral power of the alpha rhythm in the frontal and temporal leads, between the Rees-Eysenk index and the spectral power of the theta rhythm in the frontal leads., Conclusion: The results indicate the presence of the conjugation of functional changes in the brain of patients with schizophrenia with clinical manifestations of the disease and their constitutional and morphological features. Thus, the assessment of the functional state of the central nervous system in patients with schizophrenia is an important component of the diagnostic search.

The articlce addresses the spectral capacity change in low-frequency (8 – 10 Hz) and high-frequency (10 – 13 Hz) alpha ranges in reply to the presentation of smell stimuli – subthreshold, threshold and superthreshold concentration of butanol – to 22 girls. The differences in electric brains activity of the girls with different sensitivity to butanol have been found out. The differences in alpha rhythms spectral power were revealed to depend on the girls’ sensitivity and smell concentrations. The girls with high and average sensitivity to butanol react to the subthreshold concentration in alpha high-frequency rhythm.

In article the theoretical review on a problem of possibility of use of an EEG method in studying of processes of adaptation of the person is presented. It is shown that this method allows to reveal people on individual and typological groups with various degree of stability to influence of ecological and adverse factors.

Objective: To study interhemispheric asymmetry (IHA) according to electroencephalography (EEG) data of a healthy person during cognitive awakening from the second stage of daytime sleep before restoring the performance of the psychomotor test., Material and Methods: In 23 healthy adult subjects, we studied IHA in the amplitude-amplitude interaction of EEG rhythms for 20 sec segments before spontaneous awakening determined by the moment the alpha-rhythm appearance on the EEG and the subsequent onset of psychomotor activity. The state of the subject during this period (in the initial stage of the so-called cognitive awakening preceding the behavioral awakening), when the person is unable to move, but is able to perceive external stimuli, is an experimental model for highlighting signs of conscious activity of patients when coming out of a coma. Wavelet transform was used to calculate the rhythmic characteristics of bioelectrical activity. The Kendall correlation coefficient served as a measure of rhythm interaction., Results: IHA in the interaction of EEG rhythms is dynamic nature and formed by theta rhythm connections with alpha2- and beta-rhythms in the left brain hemisphere and delta-type connections in the right., Conclusion: Possibly, the greater activation of the left hemisphere is related to the retrieval of an instruction from memory, which subsequently allows to return to the activity interrupted by sleep.

The authors discuss modern ideas about the neurophysiological mechanisms of awakening from sleep and the results of own EEG studies of the spatio-temporal dynamics of the activity of the cerebral hemispheres using the own experimental model for studying consciousness in the sleep-wake paradigm. This model is based on continuous execution of a monotonous psychomotor test performed lying down with eyes closed and allows observing several short-term sleep episodes during a 1-hour experiment, followed by spontaneous awakening and restoration of the psychomotor test. A necessary condition for the restoration of activity during spontaneous awakening is the emergence of the EEG alpha rhythm, the parameters of which determine the effectiveness of the restoration of the psychomotor test and, accordingly, the achievement of a certain level of consciousness, and therefore can be considered as a neurophysiological correlate of consciousness activation upon awakening. The considered experimental model of consciousness can be useful for analyzing the neurophysiological mechanisms of consciousness activation in patients with chronic impairments of consciousness and for searching for effective methods for the rehabilitation of such patients.

Objective: Determination of differences in brain function in alcohol-dependent patients with varying degrees of inhibitory control impairment., Material and Methods: Seventy-five patients with alcohol dependence were examined. The level of inhibitory control was assessed using the Go/No-go test. The background electric activity of the brain was recorded, and the values of spectral power and coherence of theta, alpha, and beta rhythms were analyzed. Two groups of patients - 24 with- and 51 without inhibitory control impairment - were determined., Results: According to the spectral analysis, high values of alpha rhythm in the frontal-central-parietal-occipital and beta rhythm in the central and left occipital cortex, low values of theta rhythm in the posterior-temporal regions were common for patients with inhibitory control impairment. Visual analysis of the EEG in patients with inhibitory control impairment shows a smoothing of zonal differences in the alpha rhythm, which is not found in patients without the disturbance of inhibitory control. Patients with inhibitory control impairment were characterized by an increase in interhemispheric connections in the alpha and beta frequency ranges and a weakening of intrahemispheric connections on the right in the theta rhythm range., Conclusion: There are significant differences in the functioning of the brain in patients with alcoholism, depending on the presence / absence of inhibitory control impairment.

This paper presents findings of the comparative computer analysis of brain bioelectrical activity (EEG) in three groups of rural population, which include: long-livers, their close relatives, and representatives of families without records of longevity (the latter was conventionally accepted as the «control group»). Registration of EEG was carried out in conditions of quiet wakefulness with eyes closed. For each group, the average spectral power, frequency characteristics, EEG indices in the ranges of δ-, θ-, α- and β-rhythms were estimated. The results have revealed the increased ascending effects of the synchronizing link and the weakening of the activating assumptions of non-specific brain systems in long-livers, which we consider as reflection of inhibitory mechanisms which are required to replenish the mobilization resources. With regard to the group of relatives, there were revealed a smaller percentage of δ-rhythm and a greater severity of the α-rhythm index in the temporal areas, as compared to the control group, which is indicative of a more optimal level of processes responsible for memory, integration of afferent (auditory and visual) information and harmonization of the emotional background.

Aim: To identify neurophysiological markers of focal and generalized epileptic seizures in the inter-epileptic period., Material and Methods: Sixty-four patients, including 36 with isolated generalized tonic-clonic seizures and 28 with focal seizures, were examined. The control group consisted of 27 healthy people. EEG-video monitoring and bioelectric activity analysis of the brain during wakefulness and day sleep, spectral EEG analysis, quantitative and quality indicators of sleep were used., Results and Conclusion: In generalized epileptic seizures, alpha rhythm is predominantly recorded in the left hemisphere. In wakefulness, the focal epileptiform activity develops during the first two stages of day sleep. In focal epileptic seizures, delta and beta-2 rhythms were recorded in the left hemisphere, regional epileptiform changes are aggravated during the 1st and 2nd stages of slow sleep initiated in the frontal regions. A focal component of the epileptiform activity in the inter-epileptic period in patients with different types of seizures should be taken into account in examination and treatment planning of patients who had difficulties with the diagnosis of epilepsy type.

We studied the psychophysiological status (cognitive, psychoemotional and neurodynamic parameters), the power spectrum of EEG and heart rate variability of 18-23-year-old athletes, before and after a course of audiovisual stimulation (AVS) (experimental group) in comparison with sportsmen who did not receive AVS (control group). It was shown that a course of AVS (experimental group) has positive effect on psycho-emotional parameters (the levels of anxiety and neuroticism decreased; motivation to make progress and the level of hardiness increased), cognitive and neurodynamic parameters (the capacity of mechanical memory, the speed of attention switching and of a simple sensor-motor response increase; the range of fluctuation of reactions to a moving object is reduced). We also observed an increase in the power of α2 rhythm of EEG, the activity of parasympathetic nervous system and the influence of autonomic circuit of regulation in the experimental group; resting cardiac performance was more conservative as compared with the control group. We concluded that a course of AVS has positive effect on psychophysiological parameters and the mechanisms of autonomic heart regulation in athletes.

We used the ratio of spectral characteristics of the EEG alpha and beta frequencies recorded in 10 apparently healthy subjects (university students) to control a computer cursor in the graphic interface in three scenarios with the use of neurofeedback. Our results showed that the scenario which uses the power of alpha- and beta-2-frequencies provided the highest accuracy and the best speed control. The parameters of beta-1-frequency were found to be less effective since an increase or a decrease of their power could result from an increase or a decrease of the power of alpha- and beta-2-frequencies. However, the subjects got the skill of cursor control with efficiency of 81%, gradually growing during learning, after a relatively short period of time (5 trainings per 2 weeks).

EEG study of 5-7 years boys with autism revealed lower values of coherence in background delta, theta and alpha bands and higher values of coherence in background beta 1, beta 2 and gamma bands. Healthy boys showed higher values of beta and gamma coherence during cognitive task. Autistic persons demonstrated higher values of theta coherence during cognitive task.

The EEG recording from 30 supine volunterrs during bicycle ergometry with the load growing incrementally to a submaximal heart rate was made in order to study alpha spectra and their interhemispheric differences. Comparative analysis of EEG records demonstrated a statistical gain of the alpha-power in both hemispheres at the final step of aerobic work and throughout the period of recovery with power reaching the highest values in the left hemisphere. Analysis of interhemispheric differences points to activation of the right hemisphere over the whole period of the investigation.

Objective: to examine the EEG spectral characteristics during TMS in resistant depression therapy., Material and Methods: The sample consisted of 32 depressive patients diagnosed with recurrent depressive disorder or bipolar affective disorder. TMS, as well as EEG, were conducted during the previous inefficient thymoanaleptic therapy with reduced doses. TMS was performed in the left prefrontal cortex. Treatment course consisted of 15 procedures with 100% threshold intensity. During a single procedure, the patient received 20 cycles of stimulation pulses with the frequency of 15 Hz, duration of 20 seconds and interval of 60 seconds between single cycles. EEG was recorded with the use of the «NEURO-KM» apparatus (Russia) with band pass from 0.5 to 45 Hz and time constant of 0.3 sec before and after the course of TMS. Spectroscopic analysis of EEG was conducted using the Fast Furies Transformation analysis with average of no less than 30 periods for 2 seconds with subsequent mapping with the use of the «BRAINSYS» system (Russia)., Results and Conclusion: After conducting TMS, EEG changes were generalized and included the reconstruction of all frequencies of the electrical brain activity. However, the major changes were seen in alpha-rhythm spectrums: its index increased in all cortical areas, mostly in the occipital cortex, thereby forming the alpha-rhythm focus in these areas.

Unlabelled: Based on the results of our original study, we came to the conclusion that such readily available and objective method as electroencephalography for the examination of the patients with ischemic stroke may be useful for the analysis of the parameters of the alpha rhythm with a view to predicting the development of cognitive disorders (CD) which is important for the timely prescription of medicamental therapy and correction of the approaches to the rehabilitative treatment of these patients., Material and Methods: the present study involved 26 patients with ischemic stroke receiving there habilitative treatment and 35 healthy volunteers comprising the control group. All participant of the study underwent the neurological examination and neuropsychological testing; the stroke patients were additionally examined with the use of electroencephalography., Results: It was shown that the increase of the alpha rhythm amplitude in the anterocentral brain regions to more than 60 mV and its reduction to below 20 mV reflected the disturbed hierarchical regulation of the functioning of cerebral structures in the form of the dominant synchronized state of the brain. Its most pronounced clinical manifestations were cognitive disorders. The disturbances to the physiological gradient and the alteration of the alpha rhythm amplitude (to below 20 mV and above 60 mV) in the anterocentral brain regions accounted for the higher than 70% probability of detecting moderate CD in the patients with ischemic stroke. The amplitude of alpha rhythm in the anterocentral brain regions may serve as an indicator of the effectiveness of the consolidation of information in the process of memorization and of the speed of information retrieval; moreover, it is an objective characteristic of the patients' emotional state. It is concluded that the estimation of the amplitude of alpha rhythm in the anterocentral brain regions is needed to predict the course of CD in the patients presenting with ischemic stroke including those receiving the rehabilitative treatment., Conclusion: The detailed analysis of the electroencephalograms of the patients makes possible the well-timed correction of the individual rehabilitation program and the enhancement of the effectiveness of recovery of both cognitive and motor functions.

Functional interaction between prefrontal, temporal and tempo-parieto-occipital zones during preparation to recognition of incomplete linedrawings were analyzed in adults (n = 26) and children of 7-8 years old (n = 20). The strength of cortico-cortical interactions was estimated with the imaginary part of the complex-valued coherence at the frequency of alpha-rhythm (Jα). The Jα value was analyzed in the following three experimental conditions which corresponded to different stages of preparation to visual recognition: nonspecific sustained attention in the period preceding the cue (C1); focused attention in the period preceding a not-yet-recognized target stimulus (C2) and focused attention prior the successfully recognized stimulus (C3). When sustained attention changed to focused attention toward a target stimulus Jα increased in adults but decreased in children. Comparing Jα in the subgroups of both adults and children that showed highest recognition scores helped to uncover the age-related pattern of rearrangement of the cortico-cortical functional interactions in alpha-rhythm. That pattern was found to be hemisphere-specific and different at different stages of preparation to recognition of incomplete linedrawings. In adults, the maximal Jα were found in the left hemisphere during the period preceding the recognition of a target stimulus. At this stage of the functional preparatory tuning, in adults, Jα in the left hemisphere was significantly greater than in children. In adults, Jα related to the right hemisphere attained the highest values when attention was directed to not-yet-recognized stimuli. These values were significantly higher than similar values measured in children. In children, Jα reached its highest value during sustained attention. The characteristic pattern of functional interactions among prefrontal, temporal and temporo-parieto-occipital cortices that observed in children of 7-8 years old during preparatory functional tuning for the recognition of incomplete linedrawings is considered to be an indication of relative immaturity of mechanisms of directed voluntary attention and working memory.

This research represents MRI and EEG-investigation in children with mental disorders perinatal genesis during tDCS. In 70% cases brain structures damages don't found or were minimal. On the contrary, in 77% cases α-rhythm of EEG in parietal-occipital areas was non-regular. Functional insufficiency can as a basis of high efficiency tDCS by children. In cases with autism spectrum disorders the Subscales of Woodcock-Jonson were used for the quantitative estimation of efficiency of the course of treatment with tDCS. Positive changes after the course of tDCS were revealed in psychic state, speech comprehension, communication, practical and speech experience, fine motor skills and social integration.

Stress reactivity of the motivational system of defense can be assessed with the aid the cardiac defense response (CDR) - the reaction of the cardiovascular system to unexpected aversive unconditioned stimulus. The main objective of the study was revealing putative contribution of oscillatory systems of the brain into central pathogenic mechanisms of enhanced blood pressure (BP) stress-reactivity in naive patients with arterial hypertension (AH) of the 1st-2nd degrees (n = 17) and healthy control (n = 19) subjects. Using dynamic registration "beat-by-beat" arterial pressure, and oscillatory activity related EEG (64 channels) is estimated using the event-related synchronization/desynchronization (ERD/ERS). Along with abnormally high blood pressure in patients with hypertension background set significantly lower concentrations of serotonin blood platelets and increased tonic activation of the left hemisphere, reflected in the asymmetric reduction of delta- (2-4 Hz) and theta-1 (4-6 Hz) power in the central and parietal cortex in the hemisphere CDR of the patients are characterized by hyperactivity both short- and long-latency components of blood pressure. According to the dynamic analysis of the concomitant EEG, long-latency BP components may be accounted by, among other mechanisms, weakening of the descending ("top-down") inhibitory control, hypothetically implemented with the high-frequency EEG alpha (10-12 Hz) oscillations from the medial central-parietal cortex of both hemispheres of the brain.

The features of the electroencephalogram (EEG) at the heart rate variability single biofeedback session in adolescents aged 15-17 years living in the subpolar and polar northern regions were determined. In adolescents of the subpolar region identified shaped age EEG pattern. We have established higher diencephalic and subcortical brain structures activity manifested in the elevated theta-activity levels and the diffuse photic driving reactions in adolescents of the polar region than in adolescents of subpolar region. In the dynamics of the biofeedback sessions in both regions there were identified groups of persons with both increased alpha-activity spectral power and decreased of it. After biofeedback sessions in adolescents of polar region more prolonged increase of alpha-activity, more pronounced reduction of theta-activity and the photic driving reactions were revealed. Changes in EEG patterns are most characteristic of the right brain hemisphere involving the frontal brain areas.

A comparative spectral analysis of electroencephalograms in patients with focal and generalized epileptic seizures in the interictal period revealed some specific characteristics of these paroxysms. Slowing of dominating alpha-rhythm was seen in case of the localization of epileptiform activity in frontal-central-temporal and occipital-parietal areas with the further spreading of epileptiform activity to the temporal area. Asymmetry of dominating alpha-rhythm in the right hemisphere was found in patients with focal paroxysms, asymmetry of theta-rhythm in all patients, of beta-2 rhythm in patients over 45 years old and of delta-2 rhythm in female patients.

We investigated variability of responses to emotionally important auditory stimulation in different groups of TBI (Traumatic Brain Injury) in acute state or recovery. The patients sampling consisted of three different groups: patients in coma or vegetative state, patients with Severe and Moderate TBI in recovery period. Subjects were stimulated with auditory stimuli containing important physiological sounds (coughing, vomiting), emotional sounds (laughing, crying), nature sounds (bird song, barking), unpleasant household sounds (nails scratching the glass), natural sounds (sea, rain, fire) and neutral sounds (white noise). The background encephalographic activity was registered during at least 7 minutes. EEG was recorded while using portable device "Entsefalan". Significant differences of power of the rhythmic activity registered during the presentation of different types of stimuli were analyzed using Mathlab and Statistica 6.0. Results showed that EEG-response to the emotional stimuli differed depending on consciousness level, stimuli type, severity of TBI. Most valuable changes in EEG spectrum power for a patient with TBI were found for unpleasant auditory stimulation. Responsiveness to the pleasant stimulation could be registered in later stages of coming out of coma than to unpleasant stimulation. Alpha-activity is reducing in patients with TBI: the alpha rhythm depression is most evident in the control group, less in group after moderate TBI, and even less in group after severe TBI. Patients in coma or vegetative state didn't show any response in rhythmic power in the frequency of alpha rhythm.

In healthy adults (n = 35) was used the model the set study of recognition angry facial expression. The load on working memory by extending the interstimuli time up to 16 sec between the target (facial image) and starting (spot light) stimuli does not lead to a significant slowdown of switching of the set. Differences in the magnitude of the induced synchronization of the alpha rhythm in interstimulus period obtained in the subjects with the change in recognition of emotional facial expressions and the subjects "without errors". At the last group synchronization is clearly more pronounced. The implementation of successive cognitive acts is modulated by selective attention, whichis evident in the level of changes the induced synchronization/desynchronization of alpha range potential. The proposed mechanism "inhibitory control" provides the flexibility of cognitive processes by suppressing effect on cortical processes irrelevant factors during interstimulation pauses. This "protective" mechanism, we believe due to little effect of the loading on working memory.

Power spectra analysis EEG was used for baseline interval and during olfactory stimulation in drug dependence and healthy persons. Intergroup differences of EEG spectra were related with enhancement of cortex biopotential power in narcological patients at parietal and temporal sites. Interhemispheres features of frequency bands contribution in EEG spectra were identified. Increased biopotential power in drug dependence persons was observed at left temporal hemisphere in high-frequency bands in baseline interval and during olfactory stimulation. Increased power of alpha activity was typical for right temporal hemisphere in narcological patients as compare to healthy persons. Detected neurophysiological patterns may be related with psychological and behavioral features of addictive disorders.

Cranio-cerebral trauma is considered as one of the leading causes of mortality, long-term temporary incapacity for work and disability. The aim of the article is to study distant consequences of the so-called "combat cranio-cerebral injury". 108 male patients - participants of the military actions in Afghanistan were examined. The patients were divided into groups depending on the severity of the injury. The reasons of the development of violations of bioelectric activity of the brain in soldiers who have had a history of traumatic brain injury were analyzed. Patients underwent the EEG and the analysis of the results was carried out. The examination of bioelectric activity of the brain showed that the battle injury is characterized by changes in the frequency and amplitude of the alpha-rhythm, which proves that the dysfunction of non-specific structures of the brain is the consequences of cranio-cerebral injury.

At children 5-6, 7-8 and 10-11 years on model of cognitive set are revealed age features of influence of last experience on perception of a face expression. At children of 5-6 years rigid set on an angry face was experimentally formed: at a testing stage show set-shifting caused large number of erroneous recognition of face expression of perseverative type (assimilative illusions). Plasticity of the set raises in 7-8-year age and considerably the number of assimilative illusions decreases. On 10-11 years sets doesn't differ essentially from adult people on plasticity and a ratio of number of assimilative and contrast illusions. Changes of spatial synchronization of electric potentials teta- and alpha ranges of frequencies in all age groups it is observed generally at a stage of formation of set. On all age groups strong correlation between bioelectric data and features of the set on a face expression is revealed. These data supports the hypothesis that cortiko-hippocampal and fronto-thalamic functional systems of integration of a brain activity participate in the organization of a set on an emotional face expression and provide cognitive flexibility.

The model of cognitive set to emotionally negative facial expression was used in the study (35 young healthy subjects) of EEG events in a 8-second interval between the target and triggering stimuli. Coherence of brain potentials recorded from different cortical areas of the right and left brain hemispheres in the alpha and theta bands was analyzed in time segments within pre- and poststimulus intervals. A certain dynamics in the spatial synchronization in the alpha-band was revealed, which might reflect modulation of selective attention in time periods of the cognitive process providing its plasticity and set shift in response to a change in the situation. It is suggested that the source of attention modulation is the inner representation of the intervals between significant stimuli formed in the prefrontal cortex as a result of learning. Analysis of changes in the spatial synchronization in the theta band at individual stages of the set to angry face suggests that the corticohippocampal system is not directly involved in the time interval estimation but is linked to the emotional memory.

The paper investigated variability of individual EEG parametres: frequency of the maximum peak, width of a range and depth of reaction desynchronization (reduction alpha-rhythm of EEG at opening of eyes) in slowly increasing hypoxia from 20.9% to 10%-s' O2 of the sportsman with various types of physical activity and features of temperament. There were investigated 24 first-class athletes (11 swimmers, 13 skiers) aged 18-26 years. It is shown that dynamics of EEG rhythms during hypoxia, unlike normoxia, characterised by instability of spectral structure and phase during time of hypoxia test. It is established, that individual typological features (typology of nervous system) influence EEG response during hypoxic test. The negative relations between a psychological construct "endurance" for questionnaire (FCB-Ti) and feature alpha-rhythm EEG during hypoxia test are shown. The type of physical training and re-structuring pattern of breath (phenotypic adaptation) modulates sensitivity of brain structures to hypoxia which is reflected in dynamics alpha-rhythm of EEG in hypoxic conditions.

The time of a decision of mathematical logical tasks (MLT) was decreased during classical musical accompaniment (power 35 and 65 dB). Music 85 dB did not influence on the process of decision of MLT. Decision without the musical accompaniment led to increasing of coherent function values in beta1, beta2, gamma frequency ranges in EEG of occipital areas with prevalence in a left hemisphere. A coherence of potentials was decreased in EEG of frontal cortex. Music decreasing of making-decision time enhanced left-sided EEG asymmetry The intrahemispheric and the interhemispheric coherences of frontal cortex were increased during the decision of MLT accompanied by music. Using of musical accompaniment 85 dB produced a right-side asymmetry in EEG and formed a focus of coherent connections in EEG of temporal area of a right hemisphere.

We studied the changes of electroencephalograms (EEG) related to on-pump coronary artery bypass grafting (CABG) in 28 right-handed male patients with coronary heart disease (CHD), 10 from which had accompanying moderated (30-50%) carotid artery (CA) stenoses. All EEG studies were performed 3-5 days before and 7-11 days after CABG. EEG data of healthy age-matched males (n=14) were examined. Before surgery, the CHD patients differed from the control group by less expressed theta2 and beta1 rhythm power asymmetry. The differences demonstrated worse conditions for cognitive processes in CHD patients. After CABG, the higher power of teta1 and 2 rhythms, predominantly in the frontal lobe of the left hemisphere which was mostly expressed in patients with CA stenosis, was observed in all CHD patients. This effect can be considered as the appearance of ischemic neuronal injury caused by on-pump CABG. The localization of changes in the frontal cortex of the left hemisphere can be related to a high vulnerability of these regions. The deficit of cerebral blood flow in these regions will define a clinical picture of cognitive decline after CABG.

We compared the alpha band EEG depression (event-related desynchnization, ERD) level in two tasks, involving activation of different attentional processes: visual search for a deviant relevant stimulus among many similar ones and visual oddball. Control data for the visual search task consisted of simple viewing of several stimuli being of the same shape as the relevant stimulus in the search trials. Gaze position was verified by eye tracking method. We interpreted alpha band ERD as a correlate of activation of attentional processes. Fixating the target in visual search task caused a significantly larger ERD than fixating the same stimuli in control trials over all leads. We suppose this to be related with task and visual environment complexities. The frontal ERD domination may indicate attentional control over voluntary movements execution (top-down attention). The caudal ERD may be related with updating of visual information as a result of search process (bottom-up attention). Both relevant and irrelevant stimuli in the oddball task also induced alpha band ERD, but it was larger in response to relevant one and reached maximum level over occipital leads. Domination of caudal ERD in oddball task is supposed to indicate bottom-up attention processes.

Electroencephalography was performed in schoolchildren aged 10-12 years with emmetropia (n=38) and myopia of different degree (n=165), the goal was to study alpha-rhythm frequency, configuration and maximum amplitude. 16-channel device "Neuron-Spectr-3" (Russia) was used. Student criterion was counted with 95% confidence interval. Significant decrease of alpha-rhythm was found in children aged 10-12 years with myopia compared to control group (p < 0.05). Interhemisphere asymmetry of alpha-rhythm frequency and slowing of alpha-rhythm were revealed in schoolchildren with myopia only. Slowing and decrease of amplitude of alpha-rhythm are registered on the very early stages of myopization process before development of axial myopia.

Right hemispheric dominance of the baseline alpha-band spectral power was revealed in 5-7 years boys with autism. This feature persisted during performance of a cognitive task (counting). Also, boys with autism showed lowered level of the alpha spectral power as compared with healthy children. In healthy children, the gamma spectral power increased during performance of the cognitive task as compared to baseline state. Autistic persons showed higher values of the gamma spectral power as compared with normal boys. Boys with autism showed less expressed changes in the gamma spectral power during the cognitive task than healthy children. The reduced spectral power of the alpha band in autistic boys may serve as a precursor of conversion from autism to schizophrenia. Higher level of the gamma spectral power in autistic boys is characteristic also of schizophrenic patients with positive symptoms. Lowered levels of fast rhythms reactivity revealed in autistic boys and the same effect earlier described in schizophrenic adults probably have the similar nature.

Complex children examination with alalia was based the analysis by the role of subcortical brain structures for the formation of speech was investigated. Alalia is systemic speech underdevelopment in children, which violated all the components of speech. Evaluation of the functional state of brain structures on the EEG has allowed to distinguish the two groups, which depend on the nature of changes in bioelectric activity (BEA). The first group is one with the changes of alpha rhythm and/or local changes in BEA predominantly in the left hemisphere, the second group with violations ofbrainstem origin, mainly generalized EEG changes. A comprehensive analysis of clinical data has allowed to suggest the basis of the formation alalia lies subcortical structures lesion of the left hemisphere of the brain and stem departments of one. The analysis of perinatal risk factors has allowed to hypothesize about the connection of subcortical structures lesion with antenatal complications in the first half of pregnancy.

Spectral characteristic of the alpha activity (frequency of the maximum spectral peak) were comparatively studied in schizophrenic patients with predominance of positive or negative symptoms and healthy subjects in the resting state and during cognitive task performance. In patients with negative symptoms, the spectral peak frequency of the alpha activity (8-13 Hz) was decreased at rest as compared to healthy subjects in all cortical areas. In patients with positive symptoms, the peak frequency of the alpha rhythm in the occipital cortical areas was higher than in healthy subjects. The performance-induced increase in the alpha-rhythm peak frequency during cognitive tasks was less expressed in schizophrenics than in healthy subjects. A correlation of these characteristics with psychopathological symptoms was revealed. The results suggest a difference in neurophysiological mechanisms underlying positive and negative symptoms in schizophrenia.

A choice between probability (100, 75, 50, 25, 10, 0%) and valuable reward were investigated in adult. In behavioral experiments, adult subjects put in a situation of a choice between greater, but risky prize and smaller, but received always, made the decision according to situational factors and specific features of character such as propensity to risk and care. In a situation of choice of behavioral strategy, subjects could be divided in "inclined to risk" and "careful". Tipologycal differences between groups were the greatest under conditions of 25% probability of getting a valuable reward. Probability prognosis was more efficient in persons "tended to risk", than in "careful" subjects. According to psychological tests, "impulsive" people appeared to be more inclined to risk than to cautiousness. For the group of persons that tended to cautiousness under conditions of 25% probability of getting a valuable reward, synchronism of EEG rhythms in the alpha and beta bands was revealed.

Features of spatial organization of neocortical potentials were studied in subjects with different decision-making time during performing the task of memorizing and subsequently reproducing, on a monitor screen, a sequence of signals. The subjects with a short decision-making time differed from those with a long decision-making time in a higher level of the intra- and interhemispheric coherence in alpha EEG frequency band different neocortical areas during reproduction of a signal sequence (coherence in the frontal, central and parietal areas; coherence between the right central and the left frontal, central, parietal, occipital and temporal areas; coherence between the left occipital and both the frontal areas).

The test-retest study of the individual alpha peak frequency (IAPF) variability was provided in eyes closed and eyes open conditions in standard (8-12 Hz) and individual alpha band range in different brain areas in 96 healthy male subjects (aged 25-40). The pairwise comparisons showed that IAPF means are not different in the left and right hemisphere sites, in eyes closed and eyes open conditions, in standard and individual alpha range. Computed in the first 5 s after opening eyes fronto-central area IAPF mean was lower than in eyes closed condition. IAPF computed in individual alpha range in posterior area in eyes closed condition had the minimal variability and was the most reproducible in test retest investigation.

Using a cognitive set to emotional facial expression as a model, induced synchronization/desynchronization of the cortical theta- and alpha-activities were studied in adult healthy people under conditions of increased load on the working memory (additional task of the verbal stimuli recognition). A correlation was found between behavioral (increase in the set rigidity) and electrophysiological (decrease of the induced theta-rhythm synchronization) data. A hypothesis is suggested that the earlier revealed increase in the tonic prestimulus theta-activity and suppression of the poststimulus phasic activation of the cortico-hippocampal system are one of the mechanisms of the decrease in plasticity of the cognitive function of the emotional facial expression recognition under conditions of the increased load on the working memory. Reciprocal relations between two functional systems of the brain activity integration (cortico-hippocampal and fronto-thalamic) in the process of recognition of emotional facial expression are discussed.

Based on the results of examination of 157 patients with neurotic depression (ICD-10 items F43.20, F43.21, F43.22), electroencephalographic criteria of transpersonal psychotherapy efficacy have been specified as following: the increase of alpha-3 activity in the frontotemporal region and the decrease of a spectral index of theta-activity in parietal, central, occipital and prefrontal regions; some changes in beta-band (the increase of spectral index of beta-1 in frontotemporal and prefrontal regions and the decrease of beta-2 in parietal and occipital regions). The direction of these changes is objectively supported by the clinical dynamics, data of correlation analysis of neurophysiological parameters and psychometric scales used for assessment of the presence and severity of emotional and personality disorders.

Fifty-five patients with neurotic and neurosis-like disorders and 20 healthy controls, aged 17-64 years, have been examined. The basic research method was electroencephalography (EEG) with the fractal analysis of alpha power fluctuations. In patients, the changes in the fractal structure were of the same direction: the decrease of fractal indexes of low-frequency fluctuations and the increase of fractal indexes of mid-frequency fluctuations. Patients with neurosis-like disorders, in comparison to those with neurotic disorders, were characterized by more expressed (quantitative) changes in fractal structures of more extended character. It suggests the presence of deeper pathological changes in patients with neurosis-like disorders.

The aim of the study was to find the diurnal changes in the EEG alpha-activity in patients with endogenous depressions. Both morning and evening EEG records were characterized by the transition of modal value of leading rhythm into the lower frequency band (9-10 Hz versus 10-11 Hz in healthy people). The spectral power of alpha-rhythm was higher, especially in the occipital cortical areas, in the morning hours than in the evening. In the morning, the intrahemispheric differences in the alpha-rhythm power in occipital areas were leveled out while in the evening hours, the normalization of intrahemispheric balance with higher power of alpha-rhythm in the right occipital area was seen. A comparative analysis of mean values of coherence (COH) in cortical areas in patients revealed higher COH values in parietal-central areas of both hemispheres, as well as in frontal- and right middle temporal areas, in the morning compared to those in the evening. COH values were lower in the morning than in the evening in occipital and posterior temporal areas. The mean COH value of alpha-rhythm in the right hemisphere was higher compared to the left hemisphere both in the morning and in the evening.

We examined temporal dynamics of EEG phase-locked alpha oscillations during perception of illusory (Kanizsa square) and non-illusory images in boys with autism and age-matched typically developing boys. In typically developing boys the illusory contour (IC) as compared to the control stimulus provoked an increased alpha response at the parietal scalp areas. This IC effect demonstrated continuity within the time window of 133-267 ms after the stimulus onset. Although boys with autism did not display this effect at the group level, part of the sample showed an atypical two-stage pattern of illusory contour effect. The first early stage of IC effect (50-133 ms) was pronounced at the midline occipital electrode localized in the vicinity of the primary visual cortex. The localization and the early onset time suggest that this early IC effect is related to abnormally enhanced "low-level" locally-oriented processes of contour completion in autism. The second stage of IC effect (267-400 ms) was observed at the left parietal region only, and was delayed comparatively to that in healthy boys, suggesting the deficit of "intermediate" processes of perceptual grouping linked to the higher-order visual areas.

Specific changes of bioelectrical brain activity was found in 27 patients with different level of posttraumatic consciousness depression by the methods of crosscorrelation, coherence and factor analysis of EEG. The changes of activity of morphofunctional systems of intracerebral integrations were revealed partially by decreasing of unspecific activity from brainstem structures reflected with increasing of slow wave activity and decreasing of EEG coherence in alpha- and beta-range. Depression of system organization of interconnections of bioelectrical brain activity in frontal and occipital regions of both hemispheres was also detected, and testified about decreasing of intercortical and thalamocortical brain system action under brain dislocation. The changes of integrative brain system activity, provides interhemispheric interaction, had the specific characted. Our results propose a "facilitation" of activity of system, providing "direct" interhemispheric connections through corpus callosum and other commissural tracts of telencephalon as a sequel of mesodiencephalon structures depression with steady reciprocal, antiphase relations of slow weve activity in symmetrical areas of hemispheres in coma II patients. The data of our research had shown no complete disintegration of system brain activity in coma II patients in spite of consciousness and brainstem reflexes depression.

The effect of increased working memory load (introduction of additional cognitive task into the context) was studied in adult healthy subjects (n = 35, 16 men, 19 women) in experiments with cognitive set. The EEG coherence in the frequency bands theta (4-7 Hz) and alpha (8-13 Hz), as well as alphal (8-10 Hz) and alpha2 (11-13 Hz) was analyzed and compared to the control data obtained in the experiments without additional memory load. Additional memory load was accompanied by an increase in the rigidity of the set to facial expression and substantial change in the pattern of the spatial synchronization of cortical potentials: coherence of potentials in the theta bands increased between the left and right frontal areas and between the frontal and temporal areas. A hypothesis is suggested that the rigidity of the set to emotionally negative facial expression is associated with the activation of the cortico-hippocampal system, which is justified by a substantial increase in coherence in the theta band in the frontal area known as the key structure in the functioning of cognitive sets. Loading the working memory is associated also with substantial weakening of the spatial synchronization of the low-frequency alpha rhythm, which presumably reflects the increase in the role of the fronto-thalamic system of selective attention in the process of recognition due to redistribution of attention induced by the additional cognitive task included in the context of current activity of a subject.

We have studied 128 adolescents, aged 15-16 years, with attention-deficit hyperactivity disorder (ADHD) using clinico-psychopathological, psychometric and electroencephalographic methods. Taking into account the age dynamics, the following components of ADHD have been singled out: motor (impulsivity-hyperactivity), subjective-cognitive (attention deficit) and somato-autonomic. The significance of subjective-cognitive disturbances, along with neurophysiological dysfunction, in the ADHD pathogenesis has been proved. Quantitative (productivity deficit) and qualitative (concentration deficit) disorders have been assessed. Author substantiated the deficit of emotional-motivational self-regulation measured by the M. Luscher test and the Self-assessment scale. The specific for ADHD pattern of alpha-rhythm reactivity has been found in EEG.

To assess objectively a dynamics of brain functional state, EEG spectral power and peak latency of the P300 component of cognitive auditory evoked potentials have been analyzed in adolescents during the course of nootropic therapy of residual asthenic consequences of traumatic brain injury (ICD-10 F07.2). The study included 76 adolescents, aged 12-18 years, who have undergone severe closed head trauma with brain commotion 1/2--5 years ago. Patients have been divided into 3 groups treated during one month with cerebrolysin, piracetam or magne-B6, respectively. After the end of the nootropic therapy, 77% of patients treated with cerebrolysin as well as 50% of patients treated with piracetam and magne-B6 have demonstrated the positive dynamics of their brain functional state that manifested itself in the appearance of occipital EEG alpha rhythm or in the increase of its spectral power; in the normalization of alpha rhythm frequency; in the decrease in the spectral power of slow wave (theta and delta) EEG activity, in the amount (up to the disappearance) of paroxysmal EEG activity, in the EEG response to hyperventilation and in the shortening of the P300 peak latency. Such positive changes of neurophysiological parameters have been associated with the improvement of clinical conditions of patients and correlated significantly with the dynamics of psychometric scores of attention and memory.