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Enlarged perivascular spaces (EPVS) are increasingly recognized as an MRI detectable feature of neuroinflammatory processes and age-related neurodegenerative changes. Understanding perivascular characteristics in healthy individuals is crucial for their applicability as a reference for pathological changes. Limited data exists on the EPVS load and interhemispheric asymmetry in distribution among young healthy subjects. Despite the known impact of hydration on brain morphometric studies, blood plasma osmolality's effect on EPVS remains unexplored.This study investigated the influence of age, total intracranial volume (TIV), and blood plasma osmolality on EPVS characteristics in 59 healthy adults, each undergoing MRI and osmolality assessment twice within 14.8 months (mean ± 4 months). EPVS analysis was conducted in the centrum semiovale using high-resolution automated segmentation, followed by an optimization algorithm to enhance EPVS segmentation accuracy. Linear Mixed Effects model was used for the statistical analysis, which unveiled significant inter-individual variability in EPVS load and inter-hemispheric asymmetry. EPVS volume increased with age, higher TIV and lower blood plasma osmolality levels. Our findings offer valuable insights into EPVS characteristics among the healthy population, establishing a foundation to further explore age-related and pathological changes.

Abstract A comprehensive statistical study is conducted on O+ and H+ outflows obtained from the TEAMS/FAST data during the 23rd solar cycle (1996–2007). The study investigates interhemispheric asymmetry in ionospheric outflows during local summer, winter, and equinox seasons. Data are classified into two distinct periods: the pre‐storm and geomagnetic storm phases. Numerous statistical asymmetries are identified. The findings indicate that the dayside cusp consistently demonstrates more outflow rates of O+ and H+ in the northern hemisphere than southern hemisphere during geomagnetic storms in all seasons as well as during the pre‐storm period in the summer season with the exception of H+ during summer storms. Conversely, the nightside O+ and H+ outflow rates are higher in the southern hemisphere during pre‐storm and storm periods in the summer season. Additionally, the dawnside and duskside outflow rates of O+ and H+ are predominantly stronger in the southern hemisphere.

The purpose of the study was a theoretical review of the problem of interhemispheric asymmetry and lateral preferences in children with intellectual disabilities. Data analysis from numerous studies in neuropsychology have allowed a new view of the possibility of developing compensatory mechanisms for various disorders of higher mental functions with specific features of the lateral organization profile types of motor and sensory functions that play a basic role in the mental development of children with disabilities. The analysis of the presented scientific approaches and factual studies allow to state the presence of hidden contradictions in the issues of determining correlations of interhemispheric asymmetry in impaired development. The review of the literature presented in this paper proves the presence of qualitative peculiarities of the organization of movements in brain of schoolchildren with intellectual disabilities. At the same time, the theoretical analysis revealed a lack of consensus on the influence of lateral preferences in the difficulties encountered, which determines the relevance and necessity of further search for opportunities to use neuropsychological data and the individual lateral preferences in the development of movement skills.

The solar wind and its embedded magnetic field, the interplanetary magnetic field (IMF) together with magnetic reconnection power the large-scale plasma and magnetic flux circulation in the Earth’s magnetosphere-ionosphere system. This circulation is termed as convection and its strength is controlled by the north-south IMF component (IMF Bz). In recent years, an interest has arisen to investigate the lesser-known role of the dusk-dawn component (IMF By) in convection. It has been previously known though that prevailing nonzero IMF By can cause plasma flow asymmetries in the high-latitude ionosphere, but how the magnetospheric flows, for instance, in the magnetotail plasma sheet are affected, remains to be investigated. In this article, we introduce the recent progress and the latest achievements in the research of the influence of IMF By on tail plasma sheet convection. The research progress has been rapid and it has revealed that both fast and slow convection are affected in a manner that is in accordance with the asymmetries observed in the ionospheric convection. The results indicate the significance of the IMF By component on magnetospheric convection and they represent a major advance in the field of solar wind-magnetosphere coupling.

The article deals with the influence of systematic physical training and sport on the concentration of attention and interhemispheric asymmetry in the students of the higher education educational institution aged 19–20 years. The review of the literature corresponding to the research issue is given. The Amatuni test was used for the practical physiological study. On the basis of the study the author has made conclusions about the impact of physical education and sports on the mental activity of students.

Using the total electron content (TEC) observations from GPS, and simulations from the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIEGCM), this work investigates the large-scale traveling ionospheric disturbances (LSTIDs) and the possible involved drivers during the geomagnetic storm on January 14-15, 2022. Based on the term analysis of O+ continuity equation in TIEGCM, it is found that the traveling atmospheric disturbances in equatorward winds are responsible for the LSTIDs, with minor contributions from plasma drifts owing to the prompt penetration electric field. A strong interhemispheric asymmetry of the LSTIDs is observed, which might be attributed to both the equatorward wind disturbances and background plasma. The stronger wind (plasma) disturbances occurs in the winter hemisphere than that in the summer hemisphere. The maximum magnitude of LSTIDs in electron density disturbances occurs at ∼250 and ∼270 km in the northern and southern hemispheres, respectively, owing to both the thermospheric equatorward winds and background plasma. An interesting phenomenon that tail-like LSTIDs occur at the dip equator and low latitudes might be related to the eruption of the Tonga volcano, but it is not well reproduced in TIEGCM that deserves further exploration in a future study.

Background. The neuropsychological approach suggests that differences in cognitive processes are associated with the variability of combinations of signs of partial dominance of certain brain structures, manifested in the form of individual laterality profiles. However, the problem of identifying and studying the relationship between interhemispheric asymmetry and cognitive functions in adolescents with a high level of intelligence remains not fully resolved, which determines the relevance of this study.The aim of the research was to describe the relationship between the type of profile of interhemispheric asymmetry with the characteristics of cognitive functions in adolescents with average and high levels of intelligence.Materials and methods. The sample included 52 people aged 12–15 years: 26 adolescents with high level intelligence (main group), 26 adolescents with an average level of intelligence (control group). The following research methods were used: Wechsler test (WISC-IV), method for studying the profile of interhemispheric asymmetry (Khomskaya E.D., Efimova I.V.); method “Correction test” by B. Bourdon; method ”Story on a given topic”.Results. The majority of adolescents with a high level of intelligence revealed the severity of right-lateral features, which were traced in the manual, auditory and visual spheres of sensorimotor asymmetry. At the same time, the severity of right-lateral and ambilateral features is accompanied by more pronounced indicators of the development of cognitive functions. Adolescents with the type of profile of interhemispheric asymmetry “Left-handed” were characterized by an insufficient level of attention stability and a reduced ability for detailed speech utterance, regardless of the level of intelligence.Conclusions. The data obtained show that the peculiarity of individual profiles of interhemispheric asymmetry determines the uneven development of a number of mental functions in adolescence and the different readiness of brain mechanisms to support various cognitive processes. We assume that the results of the work will expand the understanding of the role of interhemispheric asymmetry of the brain in the organization of cognitive functions in adolescents with a high level of intelligence.

The work is devoted to one of the most relevant problems of ophthalmology and neurophysiology which is the study of interhemispheric interactions in children with ophthalmopathology.The purpose of this work is to study lateral phenotypes in children with ophthalmopathology.Patients and methods. 374 6–15 years old children were observed: 1) 160 children with non-paralytic strabismus; 2) 111 children with organic pathology of the retina and the optic nerve; 3) 103 children of the control group (without ophthalmopathology). The lateral phenotype (LP) was determined according to the scheme “dominant hand — dominant ear — dominant eye”.Results. Different LP ratios were obtained in the examined groups of children (p < 0.001). The ratio of right-handers / left-handers / ambidextrous children was most uniform in the group of children with non-paralytic strabismus (43,8 / 22,5 / 33,7 %). In the group of children with organic ophthalmopathology it was “shifted” to the right-hand side (65,8 / 10,8 / 23,4 %). In the control group the number of left-handers was minimal, and the number of ambidextrous was maximal (51,4 / 3,9 / 44,7).Conclusion. It was found that children with organic ophthalmopathology are characterized by the most pronounced predominance of right-sided LP, and children with non-paralytic strabismus are characterized by a relatively uniform distribution of right-sided, left-sided and symmetrical LP. The identified features may reflect increased left-hemispheric activity in children with organic ophthalmopathology and adaptivecompensatory increase in right-hemispheric activity in children with non-paralytic strabismus.

Introduction. In neuropsychological practice the dichotic listening task has been widely used for more than 50 years as a valid test for determining the laterality of auditory speech asymmetry. Theoretical analysis. Most of the studies of the dichotic listening task in aphasia are characterized by small sample groups, a wide demographic features of them, lack attention to the type and aphasia severity, a size of local brain damage as well. Without taking into account these important factors it is difficult to answer to some questions: 1. whether the vector of auditory speech asymmetry is determined by the age, type and aphasia severity; 2. whether the laterality of auditory speech asymmetry affects the dynamics of aphasia recovery. The aim of the study: the connection between quantitative parameters of the dichotic listening task and the dynamics of aphasia regression. Empirical analysis. Material. The study involved patients (N = 109) with traumatic and post-stroke efferent motor (50.7 ± 10.1 years) and acoustic mnestic (54.4 ± 8.2 years) aphasia of mild and moderate severity of speech disorders. Methods. Kimura’s dichotic listening task modified by B. S. Kotik; the quantitative assessment of speech in aphasia L. S. Tsvetkova, T. V. Akhutina, N. M. Pylaeva. The speech assessment was carried out twice: before and after a 6-week course of speech rehabilitation. Results. Between efferent motor and acoustic mnestic aphasia groups the difference in the laterality of ear superiority was revealed. The efferent motor aphasia group shows the ambidextrous pattern in auditory perception. The dichotic listening task efficiency increases with a burst of the left ear productivity and vice versa with the right ear. The acoustic mnestic aphasia group presents a pronounced effect of the right ear suppression. Its productivity is significantly lower than the productivity of the left ear and the same indicator of the efferent motor aphasia group. The effectiveness of the dichotic listening task in the acoustic mnestic aphasia group does not exhibit a correlation with the parameters of productivity of the right or left ear. The aphasia groups vary in the dynamics of aphasia regression. In the acoustic mnestic aphasia group, this dynamics was 2.5 times higher than in the efferent motor aphasia group. Conclusion. The right hemisphere laterality in auditory speech perception correlates positively with the dynamics of aphasia regression. Further research should find an answer to the question of the constellations of significant factors and their hierarchical relationships that could determine the positive dynamics of recovery of aphasic disorders.

Purpose. To study the dynamics of interhemispheric interactions in children with friendly strabismus as a result of functional treatment. Material and methods. The study included 135 children aged 6 to 8 (average 6.8±0.1) years with convergent non-paralytic operated strabismus in combination with hypermetropic refraction and 96 children of the same age in the control group (average 7.1±0.1 years) without ophthalmic pathology. In children with strabismus, the leading hand and dominant eye were determined before and after functional treatment. Characteristics of spatial perception were evaluated by copying of complex geometric shapes which were Taylor’s (right-handed) and Ray-Osterritz’s (left-handed). Results. After functional treatment in the group of children with non-paralytic strabismus, along with improved binocular functions and improved performance of the Taylor and Ray-Osterritz tests, there was an increase in the number of ambidextrous children and a significant decrease in the number of left-handers (p

With an ageing of population and a splurging epidemic of diabetes mellitus (DM), the prevalence of complications associated with pathology of the central nervous system are expected to increase, which in the future may have serious consequences for public health. It is known that one of the main manifestations of brain damage in type 1 diabetes is cognitive impairment, which is possibly associated with the peculiarities of vascularization and interhemispheric asymmetry, which requires in-depth analysis using modern neuroimaging methods. The aim of the study is to assess the symmetry of structural, metabolic and neurovascularization changes in the brain in patients with type 1 diabetes and cognitive impairment. The study included 120 patients with type 1 diabetes aged 18 to 45 years suffering from cognitive impairment, and 30 people without cognitive decline and the control group (n=30) healthy people without diabetes. Neuropsychological testing included the Montreal Cognitive Dysfunction Assessment Scale (MoCA test). For neuroimaging methods, standard magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), contrast and non-contrast-enhanced perfusion were used. Statistical processing was carried out using the SPSS Statistic 2020 software. In patients with type 1 diabetes with cognitive impairment, as manifested by impaired memory and/or attention, perfusion imaging revealed the presence of brain asymmetry zones. Standard MRI allowed to demonstrate changes in the white, gray matter and hippocampus in the right hemisphere. The results obtained were refined taking into account the topical localization, so during the perfusion study, regions with asymmetric blood flow were identified - namely, the white matter of the frontal lobe and the gray matter in the occipital lobe. Spectroscopy of the brain revealed that it was in these areas of the brain that the most significant metabolic disorders were noted – in the form of significantly altered ratio of N-acetylaspartate (NAA)/choline (Cho) on the left, along with the asymmetry in phosphocreatine level (Cr 2) on the right. In conclusion, early preclinical predictive diagnostics with the use of modern neuroimaging methods allows for timely detection of impaired vascularization and brain metabolism in this group of patients, However, decreased perfusion in the region within the region of frontal lobe white matter and temporal lobe grey matter, and hippocampal cell metabolism by spectra should be highlighted among the parameters Cr right and NAA/Cho left.

Polar electrodynamics is largely controlled by solar wind and magnetospheric forcing. Different conditions can make plasma convection and magnetic field disturbances asymmetric between hemispheres. So far, these asymmetries have been studied in isolation. We present an explanation of how they are linked via displacements of magnetic field line footpoints between hemispheres, under the assumption of ideal magnetohydrodynamics. This displacement has so far been studied only on a point by point basis; here we generalize the concept to a 2D displacement vector field. We estimate displacement fields from average patterns of ionospheric convection using the Weimer et al. (J. Geophys. Res., 2005a, 110, A05306) model. These estimates confirm that the influence of the interplanetary magnetic field extends deep into the magnetosphere, as predicted by models and in-situ observations. Contrary to predictions, the displacement associated with dipole tilt appears uniform across the nightside, and it exceeds the effect of IMF By. While more research is needed to confirm these specific findings, our results demonstrate how ionospheric observations can be used to infer magnetospheric morphology, and that the displacement field is a critical component for understanding geospace as a coupled two-hemisphere system.

Justification. Mental retardation is a persistent decrease in human cognitive activity against the background of organic damage to the central nervous system. Neurophysiological diagnostics, in particular electroencephalography (EEG), most adequately reflects the morpho-functional state of the central nervous system, which is the basis of the mechanisms of mental activity, and the originality of the bioelectrical activity of the brain can be considered as the main indicator that determines a decrease in the level of intellectual development and, thereby, characterizes this state. This provision actualizes the search for highly informative indicators of the originality of the bioelectrical activity of the brain in children with intellectual disabilities. Purspose. With the use of periodometric analysis investigate EEG’s indicators and interhemispheric asymmetry of rhythms amplitudes in MR patients. Materials and methods. The EEG was recorded in a state of calm wakefulness with closed eyes with Neuron-Spectrum-2 electroencephalograph. Differences in indicators were tracked using the calculation of the coefficient of compliance (CC), EEG functional asymmetry coefficients in amplitude were determined, too. Results. It was revealed that in MR patients the amplitudes of the rhythms were greater than in healthy subjects. The greatest increase was determined in theta rhythm in the anterior temporal and posterior temporal leads in the left hemispheres. Duration indices in the delta, theta and alpha ranges of the EEG in mental retardation compared with the control group were increased, and the indices of the duration of beta rhythms - decreased. When analyzing FMPA in MR persons it turned out that in right-handers the negativeness of FMPA indices increased, and in left-handers there was an increase in the positivity of FMPA indices. Conclusions 1. With mental retardation, the amplitudes of the rhythms were greater than in healthy people. The greatest increase was determined in theta rhythm in the anterior temporal and posterior temporal leads in the left hemispheres. 2. The indices of duration in the delta, theta and alpha ranges of the EEG of MR subjects were increased, and the indices of the duration of beta rhythms – decreased. 3. When analyzing FMPA in MR persons, it turned out that in right-handers the negativeness of FMPA indices increased, and in left-handers there was an increase in the positivity of FMPA indices.

Abstract Background The purpose of this review is to provide a comprehensive overview of the findings of clinical electrophysiology studies aimed to investigate changes in information processing of migraine with aura patients. Main body Abnormalities in alpha rhythm power and symmetry, the presence of slowing, and increased information flow in a wide range of frequency bands often characterize the spontaneous EEG activity of MA. Higher grand-average cortical response amplitudes, an increased interhemispheric response asymmetry, and lack of amplitude habituation were less consistently demonstrated in response to any kind of sensory stimulation in MA patients. Studies with single-pulse and repetitive transcranial magnetic stimulation (TMS) have reported abnormal cortical responsivity manifesting as greater motor evoked potential (MEP) amplitude, lower threshold for phosphenes production, and paradoxical effects in response to both depressing or enhancing repetitive TMS methodologies. Studies of the trigeminal system in MA are sparse and the few available showed lack of blink reflex habituation and abnormal findings on SFEMG reflecting subclinical, probably inherited, dysfunctions of neuromuscular transmission. The limited studies that were able to investigate patients during the aura revealed suppression of evoked potentials, desynchronization in extrastriate areas and in the temporal lobe, and large variations in direct current potentials with magnetoelectroencephalography. Contrary to what has been observed in the most common forms of migraine, patients with familial hemiplegic migraine show greater habituation in response to visual and trigeminal stimuli, as well as a higher motor threshold and a lower MEP amplitude than healthy subjects. Conclusion Since most of the electrophysiological abnormalities mentioned above were more frequently present and had a greater amplitude in migraine with aura than in migraine without aura, neurophysiological techniques have been shown to be of great help in the search for the pathophysiological basis of migraine aura.

Emotional decoding and automatic identification of major depressive disorder (MDD) are helpful for the timely diagnosis of the disease. Electroencephalography (EEG) is sensitive to changes in the functional state of the human brain, showing its potential to help doctors diagnose MDD. In this paper, an approach for identifying MDD by fusing interhemispheric asymmetry and cross-correlation with EEG signals is proposed and tested on 32 subjects [16 patients with MDD and 16 healthy controls (HCs)]. First, the structural features and connectivity features of the θ-, α-, and β-frequency bands are extracted on the preprocessed and segmented EEG signals. Second, the structural feature matrix of the θ-, α-, and β-frequency bands are added to and subtracted from the connectivity feature matrix to obtain mixed features. Finally, the structural features, connectivity features, and the mixed features are fed to three classifiers to select suitable features for the classification, and it is found that our mode achieves the best classification results using the mixed features. The results are also compared with those from some state-of-the-art methods, and we achieved an accuracy of 94.13%, a sensitivity of 95.74%, a specificity of 93.52%, and an F1-score (f1) of 95.62% on the data from Beijing Anding Hospital, Capital Medical University. The study could be generalized to develop a system that may be helpful in clinical purposes.

We undertook this observational study among 435 patients (365 men and 70 women) who were divided into 3 groups based on the severity of the brain damage (clinical features and results of neuropsychological assessment, magnetic resonance imaging, electroenchephalography, transcortical Doppler): 1. Patients with alcohol dependence syndrome F10.2х) without comorbid psychiatric disorders; 2. Patients with alcohol dependence syndrome F10.2х) and mild comorbid organic brain disorder F06.7x; 3. Patients with alcohol dependence syndrome F10.2х) and moderate comorbid organic brain disorder (F06.7x). We assessed the severity of emotional disorders, alexithymia and interhemispheric asymmetry and compared these features between the groups. We found that the severity of the organic brain damage play important role in the association between the interhemispheric asymmetry and the severity of emotional disorders and alexithymia in patients with alcohol dependence. The complex analysis of the data shown that left-handedness and a functional asymmetry toward the left are the protective factors for the emotional disorders and alexithymia in the group of patients without organic brain disorder. Moreover, right-sided cerebral deficiency and a functional asymmetry toward the right are associated with higher risk of the emotional disorders in patients with alcohol dependence.

The magnetogram inversion technique (MIT), developed at ISTP SB RAS more than forty years ago, has been used until recently only in the Northern Hemisphere. In recent years, MIT has been improved and extended to make instantaneous calculations of 2D distributions of electric fields, horizontal and field-aligned currents in two polar ionospheres. The calculations were carried out based on one-minute ground-based geomagnetic measurements from the worldwide network of stations in both hemispheres (SuperMAG). In this paper, this extended technique is used in the approximation of uniform ionospheric conductance and is applied for the first time to calculations of equivalent and field-aligned currents in two hemispheres through the example of the August 17, 2001 geomagnetic storm. We have obtained the main and essential result: the advanced MIT-ISTP can calculate large-scale distributions of ionospheric convection and FACs in the Northern (N) and Southern (S) polar ionospheres with a high degree of expected hemispheric similarity between these distributions. Using the said event as an example, we have established that the equivalent and field-aligned currents obtained with the advanced technique exhibit the expected dynamics of auroral electrojets and polar caps in two hemispheres. Hall current intensities in polar caps and auroral electrojets, calculated from the equivalent current function, change fairly synchronously in the N and S hemispheres throughout the magnetic storm. Both (westward and eastward) electrojets of the N hemisphere are markedly more intense than respective electrojets of the S hemisphere, and the Hall current in the north polar cap is almost twice as intense as that in the south one. This interhemispheric asymmetry is likely to be due to seasonal conductance variations, which is implicitly contained in the current function. From FAC distributions we determine auroral oval boundaries and calculate magnetic fluxes through the polar caps in the N and S hemispheres. These magnetic fluxes coincide with an accuracy of about 5% and change almost synchronously during the magnetic storm. In the N hemisphere, the magnetic flux in the dawn polar cap is more intense that that in the dusk one, and vice versa in the S hemisphere. These asymmetries (dawn–dusk and interhemispheric) in the polar caps are consistent with the theory of reconnection for IMF By>0 and with satellite images of auroral ovals; both of these asymmetries decrease during the substorm expansion phase.

Brain-computer interfaces (BCIs), based on motor imagery, are increasingly used in neurorehabilitation. However, some people cannot control BCI, predictors of this are the features of brain activity and personality traits. It is not known whether the success of BCI control is related to interhemispheric asymmetry. The study was conducted on 44 BCI-naive subjects and included one BCI session, EEG-analysis, 16PF Cattell Questionnaire, estimation of latent left-handedness, and of subjective complexity of real and imagery movements. The success of brain states recognition during imagination of left hand (LH) movement compared to the rest is higher in reserved, practical, skeptical, and not very sociable individuals. Extraversion, liveliness, and dominance are significant for the imagination of right hand (RH) movements in “pure” right-handers, and sensitivity in latent left-handers. Subjective complexity of real LH and of imagery RH movements correlates with the success of brain states recognition in the imagination of movement of LH compared to RH and depends on the level of handedness. Thus, the level of handedness is the factor influencing the success of BCI control. The data are supposed to be connected with hemispheric differences in motor control, lateralization of dopamine, and may be important for rehabilitation of patients after a stroke.

The von Economo neurons (VEN) are characterized by a large soma, spindle-like soma, with little dendritic arborization at both, the basal and apical poles. In humans, VENs have been described in the entorhinal cortex, the hippocampal formation, the anterior cingulate cortex, the rostral portion of the insula and the dorsomedial Brodmann’s area 9 (BA9). These cortical regions have been associated with cognitive functions such as social interactions, intuition and emotional processing. Previous studies that searched for the presence of these cells in the lateral frontal poles yielded negative results. The presence of VENs in other cortical areas on the medial surface of the human prefrontal cortex which share both a common functional network and similar laminar organization, led us to examine its presence in the medial portion of the frontal pole. In the present study, we used tissue samples from five postmortem subjects taken from the polar portion of BA10, on the medial surface of both hemispheres. We found VENs in the human medial BA10, although they are very scarce and dispersed. We also observed crests and walls of the gyrus to quantitatively assess: (A) interhemispheric asymmetries, (B) the VENs/pyramidal ratio, (C) the area of the soma of VENs and (D) the difference in soma area between VENs and pyramidal and fusiform cells. We found that VENs are at least seven times more abundant on the right hemisphere and at least 2.5 times more abundant in the crest than in the walls of the gyrus. The soma size of VENs in the medial frontopolar cortex is larger than that of pyramidal and fusiform cells of layer VI, and their size is larger in the walls than in the crests. Our finding might be a contribution to the understanding of the role of these neurons in the functional networks in which all the areas in which they have been found are linked. However, the particularities of VENs in the frontal pole, as their size and quantity, may also lead us to interpret the findings in the light of other positions such as van Essen’s theory of tension-based brain morphogenesis.

O objetivo do presente estudo foi avaliar os efeitos da estimulação elétrica funcional na assimetria cortical inter-hemisférica. Para tal, simultaneamente ao registro da atividade eletroencefalográfica, realizou-se eletroestimulação no antebraço direito para estimulação da extensão do indicador. A amostra consistiu de 45 sujeitos randomizados em 3 grupos de 15 sujeitos cada: grupo controle (submetido a 24 blocos de estimulação com intensidade de corrente zero), grupo 1 (24 blocos) e grupo 2 (36 blocos). A assimetria entre os pares de eletrodos F3-F4, C3-C4 e P3-P4 foi analisada ao longo dos grupos através de uma Anova. Os resultados apontaram para uma interação grupo x eletrodo e uma tendência de diminuição da assimetria inter-hemisférica após a eletroestimulação.The aim of the present study was to assess the effects of functional electrical stimulation (FES) on cortical interhemispheric asymmetry. Electrostimulation was performed on the right forearm to stimulate the extension of the index finger. EEG activity was recorded simultaneously. The sample included 45 subjects randomly divided into 3 groups of 15 subjects each: control group (submitted to 24 blocks of stimulation at a null intensity current), group 1 (24 blocks) and group 2 (36 blocks). Interhemispheric asymmetry between F3-F4, C3-C4 and P3-P4 was analyzed through an Anova. Results pointed out to a group x electrode interaction and a general tendency of asymmetry decrease after stimulation.