Beta Rhythms Research Articles

Effects of high carbon dioxide concentration on emotional processing: Based on multimodal evidence

The effects of CO2 on emotional processing are still incompletely understood, although its effects on cognitive performance are widely recognized. This study hypothesized that elevated CO2 concentration would affect the processing of different valence emotions, which leads to more negative emotions and fewer positive emotions. A within-subject experiment was conducted to compare subjective emotional scores, emotional processing behavioral performance, EEG patterns, and other physiological changes of 30 participants exposed to CO2 concentration at 600 ppm and 5000 ppm. The results suggested that CO2 concentration could affect neural arousal patterns during emotional processing, changes in blood pressure, and salivary cortisol secretion in healthy participants. Emotional experience task performance of participants was also affected by CO2, which was not statistically significant. At the high CO2 concentration, the systolic blood pressure (SBP) level was significantly lower (p = 0.005), while the salivary cortisol level was significantly higher (p = 0.037). Power spectral density analysis showed that there was a significant interaction between CO2 concentration and emotional valence for theta waves in frontal regions (p = 0.029), beta waves in temporal regions (p = 0.017), and gamma waves in frontal-parietal occipital regions (p = 0.013). The present study found that CO2 has a negative effect on emotional processing, such as reducing the speed and accuracy of emotional processing. To some extent, there are also some positive effects, like reducing emotionally-induced increases in blood pressure. This finding warrants further research.

Brainwaves and Emotional Responses to Changes in Red Eye Shadow Brightness and Saturation

Purpose: Investigating how Munsell’s primary color (i.e., red eye shadow) influences human brain and emotional responses to establish foundational data for image formation. Methods: We analyzed the relative power differences in background brainwaves due to variations in five levels of brightness and saturation for each eye both in male and female individuals in their twenties. We used the coefficient of variation for brainwaves for our analysis. In addition, we assessed the preferences for altered red eye shadow and the emotional responses to determine the average preference index. We performed statistical analysis for brainwaves and emotional evaluations using repeated measure analysis of variance in SPSS, followed by post hoc testing with Tukey’s test at a 95% confidence level. Results: The brainwave and emotional responses obtained by presenting red eye shadow brightness and saturation modification-created stimuli revealed that both men and women exhibited beta and gamma wave activation and alpha wave inactivation upon low brightness and high saturation stimuli. Men were more sensitive to brightness stimuli, whereas women displayed higher-level variability in brainwave responses upon saturation changes. Both genders preferred red eye shadows with brightness and saturation levels of 8 and 2, respectively. The perceptual image responses indicated that stimuli with low or high brightness were perceived as modern and subtle or clear and cute, respectively. Medium or high saturation stimuli were perceived as clear and natural or associated with a modern image, respectively, by both genders. Conclusion: This study demonstrated the impact of various color stimuli on the human brain and emotions. We consider the obtained results as foundational data, which could be used in future image consulting or when crafting desired image presentations.

Investigating the Relationship between Noise Exposure and Human Cognitive Performance: Attention, Stress, and Mental Workload Based on EEG Signals Using Power Spectrum Density

A pervasive environmental stressor is one that damages mental and physical health as well as cognitive abilities by producing noise at a specific frequency and level. Current noise pollution levels pose a significant threat to public health, potentially leading to impaired cognitive function, increased stress, and other negative health consequences. This study aims to investigate the relationship between noise exposure and human cognitive abilities using a comprehensive analysis of power spectrum density (PSD) derived from EEG signals. Twenty-four participants completed the experiment to identify the effect of exposure to different noise levels (55 dB, 65 dB, 70 dB, 75 dB, 80 dB, and 85 dB) and two types of continuous and intermittent noise. The Stroop Color–Word Test and the Emotive Epoch EEG are cognitive task instruments used during experiments. Behavioral performance (accuracy and response time) and power spectrum electroencephalographic density were collected and analyzed. The methodology involved collecting EEG data from participants exposed to controlled noise stimuli and a subsequent PSD analysis to uncover frequency-specific patterns associated with cognitive processes. Attention levels were measured by examining beta wave activity, while stress responses were evaluated through an alpha wave analysis. Additionally, mental workload was assessed by considering the overall distribution of PSD through the theta-to-alpha ratio. The results revealed a significant relationship between the exposure to noise types and levels and human cognitive ability. The analysis of the power spectrum density on the cognitive aspects of attention and stress yielded results indicating that participants were in the best attention condition and in a relaxed or unstressed state when exposed to noise levels of 65 dB in both continuous and intermittent noise types. For the mental workload aspect, participants exposed to both continuous and intermittent noise types at a noise level of 70 dB began to indicate the presence of mental workload. These findings supported the importance of considering the impact of environmental noise on human cognitive well-being and demonstrated the potential of EEG monitoring as an objective tool for assessing the impact of noise on cognitive performance.

Alpha and Beta Oscillations Differentially Support Word Production in a Rule-Switching Task.

Research into the role of brain oscillations in basic perceptual and cognitive functions has suggested that the alpha rhythm reflects functional inhibition while the beta rhythm reflects neural ensemble (re)activation. However, little is known regarding the generalization of these proposed fundamental operations to linguistic processes, such as speech comprehension and production. Here, we recorded magnetoencephalography in participants performing a novel rule-switching paradigm. Specifically, Dutch native speakers had to produce an alternative exemplar from the same category or a feature of a given target word embedded in spoken sentences (e.g., for the word "tuna", an exemplar from the same category-"seafood"-would be "shrimp", and a feature would be "pink"). A cue indicated the task rule-exemplar or feature-either before (pre-cue) or after (retro-cue) listening to the sentence. Alpha power during the working memory delay was lower for retro-cue compared with that for pre-cue in the left hemispheric language-related regions. Critically, alpha power negatively correlated with reaction times, suggestive of alpha facilitating task performance by regulating inhibition in regions linked to lexical retrieval. Furthermore, we observed a different spatiotemporal pattern of beta activity for exemplars versus features in the right temporoparietal regions, in line with the proposed role of beta in recruiting neural networks for the encoding of distinct categories. Overall, our study provides evidence for the generalizability of the role of alpha and beta oscillations from perceptual to more "complex, linguistic processes" and offers a novel task to investigate links between rule-switching, working memory, and word production.

The phase of tACS-entrained pre-SMA beta oscillations modulates motor inhibition

Inhibitory control has been linked to beta oscillations in the fronto-basal ganglia network. Here we aim to investigate the functional role of the phase of this oscillatory beta rhythm for successful motor inhibition. We applied 20 Hz transcranial alternating current stimulation (tACS) to the pre-supplementary motor area (pre-SMA) while presenting stop signals at 4 (Experiment 1) and 8 (Experiment 2) equidistant phases of the tACS entrained beta oscillations. Participants showed better inhibitory performance when stop signals were presented at the trough of the beta oscillation whereas their inhibitory control performance decreased with stop signals being presented at the oscillatory beta peak. These results are consistent with the communication through coherence theory, in which postsynaptic effects are thought to be greater when an input arrives at an optimal phase within the oscillatory cycle of the target neuronal population. The current study provides mechanistic insights into the neural communication principles underlying successful motor inhibition and may have implications for phase-specific interventions aimed at treating inhibitory control disorders such as PD or OCD.

The Effect of Alpha Binaural Beats Auditory Stimulation on Quantitative Electroencephalography (QEEG) and Pain Intensity among Tension-Type Headache Patients

Tension-type headaches, the most prevalent primary headaches affecting 2-5% of the population, significantly impact sufferers' well-being. These headaches present a persistent health challenge, constituting a considerable portion of neurologist outpatient visits. Effectively managing tension-type headaches remains challenging and can lead to notable morbidity if untreated. Treatment typically involves prophylactic pharmacological therapy alongside non-pharmacological interventions. Among non-medication therapies, brainwave entrainment using binaural beats emerges as a promising option for chronic headaches. This experimental research employed a pre-test and post-test design over a 5-day period (30 minutes daily) to assess Alpha Binaural Beats Auditory stimulation's impact on the QEEG pattern and pain intensity reduction in tension-type headache patients. The study, involving 32 participants, revealed a statistically significant increase in relative alpha wave power (p-value of 0.000) and a significant decrease in relative beta wave power (p-value of 0.045) after exposure to alpha binaural beats. Additionally, the Numerical Rating Scale (NRS) recorded a statistically significant decrease in pain intensity (p-value of 0.000). These findings suggest that Alpha binaural beats contribute to increased alpha wave activity, decreased beta wave activity in the QEEG pattern, and a substantial reduction in pain intensity associated with tension-type headaches. However, further research is needed to explore cumulative effects and long-term sustainability in tension-type headache patients, advancing our understanding and application of this therapy.

The Effectiveness of Neurofeedback on Improving Social Interactions and Activity of Daily Living in Children with Autism Spectrum Disorder: A Narrative Review

Context: Impairment in social interactions and daily activities of autism spectrum disorder (ASD) patients is one of the negative and important consequences of ASD. Recently, the use of non-pharmacological methods to improve behavior and rehabilitation in patients with ASD has attracted the attention of researchers and specialist physicians. According to the mentioned topic, This study aimed to evaluate the effectiveness of neurofeedback (NF) in improving social interactions and activity of daily living (ADL) in children with ASD. Evidence Acquisition: This narrative review obtained the desired results by collecting previous similar studies related to the study's primary purpose. First, 182 articles were extracted through the search of MeSH (medical subject headings) terms associated with the particular objectives of the study in international reliable databases. Then, twenty-five studies were selected as final studies considering the inclusion and exclusion criteria. Results: The results of the present study showed that NF can help to improve the performance of children with ASD through brain waves as a new treatment method based on conditioning and reinforcement. NF helps identify cognitive problems and improve cognitive processes in autistic children by improving self-regulation of the brain. In addition, NF leads to better cognitive performance by increasing beta waves and decreasing theta waves. On the other hand, increasing beta waves increases alertness, concentration, and metabolism, which can improve cognitive and social functioning. Conclusions: Based on the results, NF has a positive and significant effect in improving social interactions and ADL in children with autism spectrum disorder. Therefore, this method should be used to improve behavioral disorders and strengthen the ADL of patients with ASD, considering the side effects of pharmacological intervention methods.

Exploring Abnormal Brain Functional Connectivity in Healthy Adults, Depressive Disorder, and Generalized Anxiety Disorder through EEG Signals: A Machine Learning Approach for Triple Classification.

Depressive disorder (DD) and generalized anxiety disorder (GAD), two prominent mental health conditions, are commonly diagnosed using subjective methods such as scales and interviews. Previous research indicated that machine learning (ML) can enhance our understanding of their underlying mechanisms. This study seeks to investigate the mechanisms of DD, GAD, and healthy controls (HC) while constructing a diagnostic framework for triple classifications. Specifically, the experiment involved collecting electroencephalogram (EEG) signals from 42 DD patients, 45 GAD patients, and 38 HC adults. The Phase Lag Index (PLI) was employed to quantify brain functional connectivity and analyze differences in functional connectivity among three groups. This study also explored the impact of time window feature computations on classification performance, including the XGBoost, CatBoost, LightGBM, and ensemble models. In order to enhance classification performance, a feature optimization algorithm based on Autogluon-Tabular was proposed. The results indicate that a 12 s time window provides optimal classification performance for the three groups, achieving the highest accuracy of 97.33% with the ensemble model. The analysis further reveals a significant reorganization of the brain, with the most pronounced changes observed in the frontal lobe and beta rhythm. These findings support the hypothesis of abnormal brain functional connectivity in DD and GAD, contributing valuable insights into the neural mechanisms underlying DD and GAD.

Effect of Adding Neurofeedback to Neuromuscular Training on Brain Waves in Athletes With Chronic Ankle Instability: A Randomized Clinical Trial

Background and Aims This study evaluated the effects of neuromuscular training compared with neurofeedback and neuromuscular training on brain waves, foot and ankle ability, and pain intensity of table tennis players with chronic ankle instability. Methods This clinical trial study was conducted on 29 table tennis players with chronic ankle instability, which were randomly divided into combined neurofeedback+neuromuscular (Mean±SD age: 21.73±2.60 years, hieght: 173.42±5.57 cm, wieght: 77.10±10.42 kg) and neuromuscular groups (Mean±SD age: 22.14±2.53 years, Mean±SD height: 169.26±6.77 cm, Mean±SD weight:77.95±15.70 kg). ProComp Infiniti System and BioGraph Infiniti version 5 software were used to measure brain waves and perform neurofeedback protocol. The foot and ankle disability questionnaire and the visual analog scale were employed to assess foot and ankle ability and pain intensity, respectively. The rehabilitation protocol was performed for eight weeks. The paired t test and 1-way analysis of covariance were used for the data analyses. Results The paired t test results revealed a significant decrease in the amplitude of theta, alpha, and sensorimotor rhythm (SMR) waves in both groups (P<0.05) and an increase in the amplitude of the beta wave only in the combined group (P<0.05). In addition, ankle ability was significantly increased during daily activities and exercise in both groups (P<0.05). On the other hand, the results of a 1-way analysis of covariance indicated a significant difference between the two groups regarding theta and beta amplitudes and degree of ankle disability during exercise, and the improvement was greater in the combined group (P<0.05). Conclusion According to the results, combined exercises (neuromuscular and neurofeedback) can be used as rehabilitation in table tennis players with chronic ankle instability to correct brain waves, improve leg and ankle ability, and reduce pain.

Decoding bilingualism from resting-state oscillatory network organization.

Can lifelong bilingualism be robustly decoded from intrinsic brain connectivity? Can we determine, using a spectrally resolved approach, the oscillatory networks that better predict dual-language experience? We recorded resting-state magnetoencephalographic activity in highly proficient Spanish-Basque bilinguals and Spanish monolinguals, calculated functional connectivity at canonical frequency bands, and derived topological network properties using graph analysis. These features were fed into a machine learning classifier to establish how robustly they discriminated between the groups. The model showed excellent classification (AUC: 0.91 ± 0.12) between individuals in each group. The key drivers of classification were network strength in beta (15-30Hz) and delta (2-4Hz) rhythms. Further characterization of these networks revealed the involvement of temporal, cingulate, and fronto-parietal hubs likely underpinning the language and default-mode networks (DMNs). Complementary evidence from a correlation analysis showed that the top-ranked features that better discriminated individuals during rest also explained interindividual variability in second language (L2) proficiency within bilinguals, further supporting the robustness of the machine learning model in capturing trait-like markers of bilingualism. Overall, our results show that long-term experience with an L2 can be "brain-read" at a fine-grained level from resting-state oscillatory network organization, highlighting its pervasive impact, particularly within language and DMN networks.

Attention level monitoring based on EEG measurement

This paper reports on research into the daily use of EEG measurement, based on brain-computer interface (BCI). Its purpose is to present a series of visualized data, clearly showing the attention level of the users brainwave This method of recognizing the attention level can be used in a variety of practical ways, such as assessing students cognitive functions, detecting drivers fatigue levels, and clinical application in supervising the moods of patients, especially those with mental diseases. By attaining different dimensions of brain waves, which are sorted into alpha waves, beta waves and meditation, helping to evaluate attention levels, this device can deal with the raw data via inner codes and output relatively accurate results.

Impact of Sudden Sit-Stand Postural Switch on Electroencephalogram

Postural changes are inevitable motor behavior and physiological phenomenon. The study recorded electroencephalographic findings characterizing sudden switch from sitting to standing posture. 15 young adult males who satisfied inclusion criteria were recruited for the study. Baseline electroencephalographic tracings were obtained using Powerlab 26T at sitting position using scalp electrodes and during sudden switch from sitting to standing. The results of the study revealed sudden switch from sitting had no significant effect on alpha wave amplitude, beta wave amplitude and beta wave frequency. However, both alpha wave frequency and alpha/beta ratio decreased with sudden switch from sitting to standing position. The findings of the study indicated that sudden sitting to standing posture caused reductions in alpha wave and alpha/beta ratio.

Dexmedetomidine Sedation in Dogs: Impact on Electroencephalography, Behavior, Analgesia, and Antagonism with Atipamezole.

This study aimed to assess the impact of dexmedetomidine constant rate infusion (CRI) on key parameters in dogs. Six dogs received a 60 µg/kg/h dexmedetomidine infusion over 10 min, followed by three 15 min decremental CRIs (3, 2, and 1 µg/kg/h). A subsequent reversal phase employed 600 µg/kg/h atipamezole over 5 min. Continuous electroencephalogram (EEG) assessment, and cardiorespiratory and analgesia monitoring (every 3 min) were conducted, including analgesia evaluation through responses to electric stimulation. Dexmedetomidine induced profound sedation, evidenced by lateral recumbency and immobility. Patient State Index (PSI) decreased from awake (90.4 ± 4.3) to Phase 1 (50.9 ± 30.7), maintaining sedation (29.0 ± 18.1 to 33.1 ± 19.1 in Phases 2-4). Bradycardia (37.8 ± 3.5 bpm, lowest at Phase 3) and hypertension (133.7 ± 17.0 mmHg, highest at Phase 1) were observed, with minimal analgesia. Atipamezole promptly reversed sedation, restoring cognitive function (tail wagging behavior), and normalizing cardiovascular parameters. During atipamezole CRI, the EEG exhibited a transition from delta waves to alpha and low beta waves. This transition was observed alongside gradual increases in PSI and electromyographic activities. Additionally, spindle activities disappeared during this process. This study's results suggest potential clinical utility for EEG-guided dexmedetomidine sedation with reversal using atipamezole, warranting further investigation.

Modulating Consciousness through Awareness Training Program and Its Impacts on Psychological Stress and Age-Related Gamma Waves.

Aging often leads to awareness decline and psychological stress. Meditation, a method of modulating consciousness, may help individuals improve overall awareness and increase emotional resilience toward stress. This study explored the potential influence of the Awareness Training Program (ATP), a form of consciousness modulation, on age-related brain wave changes and psychological stress in middle-aged adults. Eighty-five participants with mild stress were recruited and randomly assigned to ATP (45.00 ± 8.00 yr) or control (46.67 ± 7.80 yr) groups, matched by age and gender. Ten-minute resting-state EEG data, obtained while the participants' eyes were closed, were collected using a 128-channel EEG system (EGI). A strong positive Pearson correlation was found between fast-wave (beta wave, 12-25 Hz; gamma wave, 25-40 Hz) EEG and age. However, after the 7-week ATP intervention, this correlation became insignificant in the ATP group. Furthermore, there was a significant reduction in stress levels, as measured by the Chinese version of the 10 item Perceived Stress Scale (PSS-10), in the ATP group. These results suggest that ATP may help modulate age-related effects on fast brain waves, as evidenced by the reduced correlation magnitude between age and gamma waves, and lower psychological stress. This suggests that ATP, as a form of consciousness modulation, may improve stress resilience and modulate age-related gamma wave changes.

SARS-CoV-2 Viral Replication Persists in the Human Lung for Several Weeks after Symptom Onset.

Rationale: In the upper respiratory tract, replicating (culturable) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is recoverable for ∼4-8 days after symptom onset, but there is a paucity of data about the frequency and duration of replicating virus in the lower respiratory tract (i.e., the human lung).Objectives: We undertook lung tissue sampling (needle biopsy) shortly after death in 42 mechanically ventilated decedents during the Beta and Delta waves. An independent group of 18 ambulatory patients served as a control group.Methods: Lung biopsy cores from decedents underwent viral culture, histopathological analysis, electron microscopy, transcriptomic profiling, and immunohistochemistry.Measurements and Main Results: Thirty-eight percent (16 of 42) of mechanically ventilated decedents had culturable virus in the lung for a median of 15 days (persisting for up to 4 wk) after symptom onset. Lung viral culture positivity was not associated with comorbidities or steroid use. Delta but not Beta variant lung culture positivity was associated with accelerated death and secondary bacterial infection (P < 0.05). Nasopharyngeal culture was negative in 23.1% (6 of 26) of decedents despite lung culture positivity. This hitherto undescribed biophenotype of lung-specific persisting viral replication was associated with an enhanced transcriptomic pulmonary proinflammatory response but with concurrent viral culture positivity.Conclusions: Concurrent rather than sequential active viral replication continues to drive a heightened proinflammatory response in the human lung beyond the second week of illness and was associated with variant-specific increased mortality and morbidity. These findings have potential implications for the design of interventional strategies and clinical management of patients with severe coronavirus disease (COVID-19).

Efficacy of Transcranial Direct Current Stimulation for Controlling of Food Craving in Subjects With Overweight or Obesity: A Pilot Study.

We aim to explore the effects of transcranial direct current stimulation (tDCS) on food craving improvement and changes in brain function associated with craving by conducting a total of 10 sessions of tDCS over a period of 2 weeks on overweight and obese subjects. A total of 15 patients who were overweight or obese (body mass index [BMI] ≥23 kg/m2) were included. Weight, BMI, neuropsychological variables, and food craving-related variables were assessed. We measured absolute and relative power in 19 channels and analyzed quantitative electroencephalography (qEEG) according to the following frequency ranges: delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-25 Hz), high beta (25-30 Hz), and gamma (30-80 Hz). After the application of tDCS, there was no significant reduction observed in weight and BMI. However, all measures related to food and eating showed a decrease in the intensity of cravings, and there was also a significant reduction in depression, anxiety, and perceived stress. In qEEG analysis, an increase in theta waves was observed in the left frontal area (F7 and F3), an increase in alpha waves in the right parietal area (P4), and a decrease in beta waves in the frontal area (FP2) and occipital area (O1). This study confirmed the beneficial effects of tDCS on food craving regulation in overweight or obese individuals and observed improved scores in psychological factors such as depression and anxiety. Furthermore, neurophysiological changes related to food craving were observed using qEEG.

EEG-based assessment of driver trust in automated vehicles

Effective collaboration between automated vehicles (AVs) and human drivers relies on maintaining an appropriate level of trust. However, real-time assessment of human trust remains a significant challenge. While initial efforts have delved into the potential use of physiological signals, such as skin conductance and heart rate, to evaluate trust, limited attention has been given to the feasibility of assessing trust through electroencephalogram (EEG) signals. This study aimed to address this issue by using EEG signals to objectively assess driver trust towards AVs. A simulated driving experiment was conducted, where driver trust was manipulated by introducing different types of AV malfunctions. Self-reported trust ratings were collected and used to classify driver trust into three levels: low, medium, and high. A total of 420 time- and frequency-domain EEG features were extracted, and nine machine learning algorithms were applied to construct driver trust assessment models. Additionally, to explore the potential of developing cost-effective models with reduced feature inputs, this study developed trust models using features solely from single brain regions: frontal, parietal, occipital, or temporal. The results showed that the best-performing model, utilizing features from the whole brain and employing the Light Gradient Boosting Machine (LightGBM) algorithm, achieved an accuracy of 88.44% and an F1-score of 78.31%. In comparison, models based on single brain regions did not achieve comparable performance to the comprehensive model. However, the frontal and parietal regions showed important potentials for developing cost-effective trust assessment models. This study also performed feature analysis on the best-performing model to identify features highly responsive to changes in trust. The results showed that an increased power of beta waves tended to indicate a lower level of trust in AVs. These findings contribute to our understanding of the neural correlates of trust in AVs and hold practical implications for the development of trust-aware AV technologies capable of adapting and responding to driver's trust levels effectively.

Electrophysiological features of bioelectrical activity of the horse brain

Purpose: to study the bioelectrical activity of the brain and determine the parameters of electroencephalograms in sports and untrained horses.Materials and methods. The object of the study were horses aged from 2 to 20 years in the amount of 150 heads. The animals were in active training and were also used for rental training in horse riding; their average weight was 550.78 kg; the breeds were Oryol Trotter, Russian Trotter, American Trotter and Hanoverian. During EEG recording, horses were restrained using a halter at the junctions. Experiments were carried out in the morning or afternoon, 1 hour before feeding/training or 1 hour after. EEG registration was carried out with patch electrodes in 6 unipolar leads using a special patented Ippolitova / Gauss helmet for recording EEG in animals, the electrodes on which are located along the projections of different lobes of the brain, which allows non-invasively, without the use of sedatives and shaving hair, to record the electrical activity of the brain . EEG recording continued for 10-15 minutes. We assessed brain rhythms using the following indicators: Rhythm severity index (RSI) – the degree of manifestation of the rhythm, the percentage of time during which a given rhythm is recorded (%). Frequency – the number of complete oscillations performed per unit of time, sec. (Hz). Amplitude is the largest deviation (from the average) value of a quantity, the range of oscillations.Results. As a result of the research and analysis of the obtained EEG data, waves of bioelectrical activity of the brain in horses were established in the following ranges: alpha rhythm (α-rhythm) – 7.1 – 13 Hz, amplitude up to 100 µV; beta-1 rhythm (low-frequency β-1 rhythm) – 13.1 – 25 Hz, amplitude – 3-5 µV; beta-2 rhythm (high-frequency β-2 rhythm) – 25.1 – 40 Hz, amplitude – 3-5 µV; delta rhythm (δ rhythm) – 0.3 – 4 Hz, amplitude up to 40 µV; theta rhythm (Ѳ-rhythm) – 4.1 – 7 Hz, amplitude about 30 µV; gamma rhythm (γ rhythm) – above 40.1 µV. When analyzing EEG rhythms in animals, the most pronounced spontaneous brain activity at rest in the horses studied is the delta rhythm in all leads and hemispheres. We observe oscillations with a frequency of 0.3–4 Hz and an amplitude of up to 40 μV. The waveform is regular, sinus. Such oscillations represent the delta rhythm.

Особенности мозговой активности хоккеистов и борцов вольного стиля в задаче по отбиванию шайб в условиях виртуальной реальности

Background. Very scarce works are devoted to the study of hockey players' brain activity, which is connected, among other things, with the large amount of motor activity in athletes and the complexity of EEG registration. Objective. The aim of the study was to investigate electroencephalographic markers (in alpha, beta, and theta EEG bands) during a puck kicking task of varying difficulty under virtual reality conditions in ice hockey players compared to freestyle wrestlers. Methods. The previously developed VR-PACE technology was used for the study, which allows practicing puck reflection skills in hockey in a virtual scene. In the study, pucks were presented in blocks (five blocks in total), the difficulty increased from block 1 to block 4, in block 5 the subjects only observed the pucks. EEG recordings were made using a wireless electroencephalograph BrainScanner V3.1 (research edition) by “NeuroDrive” throughout the entire task, analyzed by 20-second segments in each block and in each of the backgrounds (before and after). Twenty-two male subjects (average age=20, SD=2.4 years) participated in the study. Results. The results showed significant differences between the groups, as well as significant within-group differences between the “before” and “after” conditions of the experiment in terms of the Individual Alpha Frequency (IAF), as well as the average and total power of theta, alpha, and beta rhythms. The overall trend in both groups is similar (after the experiment, there is a decrease in IAF, an increase in alpha rhythm power in central and parietal electrodes, and a decrease in occipital electrodes; a decrease in theta rhythm power in frontal and occipital electrodes; and a decrease in beta rhythm across all electrodes). However, the hockey group exhibits significantly more pronounced shifts in EEG, indicating greater alertness and attention (higher powers of theta, alpha, and beta rhythms both before and after the experiment), as well as greater relaxation (higher power of mu rhythm after the experiment). Conclusions. The study examined the electroencephalographic correlates (IAF, power in the alpha, beta, and theta frequency bands of EEG) in hockey players and freestyle wrestlers while performing a task of deflecting a puck in virtual reality (VR). The dynamics of the EEG indicators indicate more efficient brain function in hockey players when performing the puck reflection task in a virtual reality setting, confirming the hypothesis of neural efficiency.

The relationship between the functional state of the brain and clinical and constitutional factors in schizophrenia

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. 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. 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. 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.