Neurophysiological Differences Research Articles

Comprehensive assessment reveals numerous clinical and neurophysiological differences between MECP2-allelic disorders.

Rett syndrome (RTT) and MECP2 duplication syndrome (MDS) result from under- and overexpression of MECP2, respectively. Preclinical studies using genetic-based treatment showed robust phenotype recovery for both MDS and RTT. However, there is a risk of converting MDS to RTT, or vice versa, if accurate MeCP2 levels are not achieved. The aim of this study was to identify biomarkers distinguishing RTT from MDS. We prospectively enrolled 11 MDS and 6 male RTT like (MRL) individuals for a panel of clinical and neurophysiological assessments over two visits, 8-10 months apart. We identified numerous clinical and physiological features as promising biomarkers. MRL individuals exhibited large amplitude whole body tremor, midline stereotypies (vs. hand flapping at sides in MDS), earlier neuromotor regression, and earlier onset but less commonly refractory epilepsy. In the neurophysiological domain, we observed several marked differences in sleep physiology between MDS/MRL and typically developing (TD) individuals including reduced sleeping time, increased delta power during rapid eye movement (REM) sleep, decreased occipital alpha and increased brain-wide delta power during wakefulness, and reduced spindle density and duration. MRL individuals also had much lower delta power during NREM 2 and 3 stages than the TD group. We found differences in spindle duration in the temporal lobes and spindle amplitude in the frontal lobes between MDS and MRL. Our study revealed distinct clinical features of MDS and MRL that can be monitored during a clinical trial and may serve as target engagement, disease progression, or safety biomarkers for interventional studies.

Sex differences in olfactory behavior and neurophysiology in Long Evans rats.

In many species, olfactory abilities in females are more acute than those in males. Studies in humans show that women have lower olfactory thresholds and are better able to discriminate and identify odors than men. In mice, odorants elicit faster activation from a larger number of olfactory bulb glomeruli in females than in males. Our study explores sex differences in olfaction in Long Evans rats from a behavioral and electrophysiological perspective. Local field potentials (LFPs) in the olfactory bulb (OB) represent the coordinated activity of bulbar neurons. Olfactory gamma (65-120 Hz) and beta (15-30 Hz) oscillations have been functionally linked to odor perception. Spontaneous and odor-evoked OB LFPs were recorded from awake rats at the same time for 12 days. Odors used included urine of both sexes and monomolecular odorants characterized previously for correlation of volatility with behavior and OB oscillations. Sampling duration in a habituation context, baseline gamma and beta power, and odor-elicited beta and gamma power were analyzed. We find that females sample odorants for a shorter duration than males (just over 1-s difference). Although baseline gamma and beta power do not show significant differences between the two sexes, odor-elicited gamma and beta power in females is significantly lower than in males. Neither sampling duration nor beta and gamma power in females varied systematically with day of estrus. We further verify that variance of these behavioral and physiological measures is not different across sexes, adding to growing evidence that researchers need not be concerned about often-claimed additional variance in female subjects.NEW & NOTEWORTHY Olfaction plays a large role in evolutionary processes. However, we know little about sex differences in olfactory bulb neurophysiology, and many scientists believe that females are more variable because of estrus. We show that female rats sniff odors for shorter durations than males and have lower power in neural oscillations related to cognition. Estrus was not related to variance in any measures. Finally, males and females show equal variance on these behavioral and physiological processes.

Differences in Network Functional Connectivity in Response to Sub-Symptomatic Exercise Between Elite Adult Athletes after Sport-Related Concussion and Healthy Matched Controls: A Pilot Study.

Resting-state electroencephalography (rsEEG) has developed as a method to explore functional network alterations related to sport-related concussion (SRC). Although exercise is an integral part of an athlete's return to sport (RTS) protocol, our understanding of the effects of exercise on (impaired) brain network activity in elite adult athletes is limited. However, this information may be beneficial to inform recovery and RTS progressions. Recording (128-channel) rsEEG datasets before and after a standardized moderate aerobic bike exercise test, this study aimed to explore functional connectivity patterns in whole brain and relevant functional networks in a group of elite adult athletes post-injury compared with healthy matched controls. The following networks were selected a priori: whole brain (68 regions of interest [ROIs]), default mode network (14 ROIs), central autonomic network (CAN, 24 ROIs), and visual network (8 ROIs). Twenty-one SRC athletes and 21 age-, sex-, sport type-, and skill level-matched healthy controls participated in this study. The SRC athletes were recruited during their RTS protocol (days since injury: 2-140 days). All athletes were able to achieve the exercise goal of reaching a moderate intensity (70% of their age-calculated maximum heart rate) while staying sub-symptomatic. Before and after exercise, functional connectivity was calculated by the phase locking value, in the alpha band (7-13 Hz). Mann-Whitney U and Wilcoxon signed rank tests were used to explore neurophysiological differences between and within groups, respectively. Whole-brain connectivity increased significantly from pre- to post-exercise within both groups (SRC: 0.264-0.284; p = 0.011 vs. controls: 0.253-0.257; p = 0.011). While CAN connectivity significantly increased only within the SRC group from pre-(0.298) to post-exercise (0.317; p = 0.003). Although all athletes reached their exercise goal without exacerbation of symptoms, the impact of exercise on the CAN appears to be greater for the SRC athletes, than matched healthy controls. The potential clinical significance of this finding is that it may have revealed an underlying mechanism for the cardiac autonomic alterations post-injury. This study merits further investigation into the CAN, as a network of interest more closely aligned with the clinical features (e.g., autonomic dysfunction) during athletes' RTS.

Processing of self-related thoughts in experienced users of classic psychedelics: A source localisation EEG study

BackgroundPsychedelics have gained increasing interest in scientific research due to their ability to induce profound alterations in perception, emotional processing and self-consciousness. However, the research regarding the functioning of individuals who use psychedelics in naturalistic contexts remains limited. AimsHere we aim to explore psychological and neurophysiological differences between naturalistic psychedelics users and non-users in terms of processing of self-related thoughts. MethodsWe use behavioural testing combined with electroencephalography (EEG) with source localisation. To mitigate potential confounding effects of personality traits and personal history which makes one willing to take psychedelics, we compared users to individuals who did not take psychedelics, but are intending to do so in the future. To ensure robustness of our results, we included two datasets collected at two different laboratories. ResultsThe results from Dataset I (N = 70) suggest that during self-related thoughts psychedelics users exhibit weaker increases in alpha and beta power in comparison to non-users, primarily in brain regions linked to processing of self-related information and memory (such as posterior cingulate cortex). However, analysis of Dataset II (N = 38) did not replicate between-group effects, possibly due to the smaller sample size and spatial resolution limitations. ConclusionsWhile non-replicability restricts interpretation of our findings, our research expands the ongoing discussion on strength and duration of the psychedelic effects, specifically in brain circuits associated with self-related processing, and its relationship to well-being. Our results fit into growing scepticism about the specificity of the role of default-mode network hubs in changes associated with psychedelics experience.

The Utility of Electroencephalograhy in Guiding General Anesthesia in Children.

Traditional pediatric anesthetic dosing using pharmacokinetic estimates based on age and weight is often imprecise, frequently leading to oversedation. Intraoperative electroencephalography (EEG) allows visualization of the brain's response to anesthetic agents in real time, facilitating precise titration of anesthetic drug doses optimized for the individual child. The goal of EEG-guided anesthesia management is to maintain an optimal state of hypnosis during various stages of the procedure while minimizing hemodynamic instability and other adverse effects of anesthesia. This is especially important in children with less predictable anesthetic requirements, such as children with atypical neurodevelopment, altered levels of consciousness before anesthesia, or those receiving total intravenous anesthesia, neuromuscular blockers, or a combination of anesthetic agents with different mechanisms of actions. Children with limited cardiorespiratory reserves and those undergoing high-risk procedures such as cardiopulmonary bypass also benefit from EEG guidance as they have a narrower therapeutic window for optimal anesthetic dosing. Various processed EEG (pEEG) monitors are available for intraoperative monitoring in children. These monitors display a pEEG index based on the manufacturer's algorithm, purportedly indicating the patient's hypnotic state. Due to differences in developmental neurophysiology and EEG dynamics in children, pEEG indices may not always reliably indicate the hypnotic state, especially in neonates and infants. Learning to interpret nonproprietary EEG parameters including the raw EEG, spectral-edge frequency 95% (SEF95), and density spectral array can prevent overreliance on pEEG indices. This review provides an overview of the advantages of EEG guidance during clinical anesthesia, including potential reduction in anesthetic dosage, prevention of EEG suppression, and reduction in peri-operative adverse events. We describe the use of nonproprietary EEG parameters in guiding anesthesia in children for various clinical end points including laryngoscopy, surgical incision, and maintenance of anesthesia, as well as sedation. We illustrate these principles with various case examples commonly encountered during pediatric anesthesia. Lastly, we discuss strategies to expand intraoperative EEG monitoring in children through education and training programs, as well as advocate for further research to assess clinical outcomes associated with EEG guidance to support its routine use in clinical care.

The P3 event-related potential increases when humans learn a strategy for motor adaptation.

Human motor learning involves cognitive strategies in addition to implicit adaptation. Differences in systems-level neurophysiology between strategy-based and implicit learning remain poorly understood. We asked how the P3 event-related potential, an electroencephalography signal known to increase during early motor learning, relates to strategy-based learning and implicit adaptation. We re-analysed data from two experiments, in which participants (n = 64) reached towards a visual target, with online visual feedback replacing vision of their moving hand. We induced learning by rotating the visual feedback. In the first experiment, feedback rotations were turned on during pairs of two consecutive trials, interspersed between non-rotated trials. In one condition, feedback was rotated relative to the actual movement, allowing participants to develop a re-aiming strategy on the second trial of each pair, while it was rotated relative to the target in the other condition, rendering re-aiming futile. P3 amplitude increased in the first rotated trial in both conditions, but this increase was more pronounced in the re-aiming condition. In the second experiment, a constant visuomotor rotation was turned on for many consecutive trials. We instructed one group beforehand how to re-aim successfully, while the other group had to develop a strategy by themselves. P3 amplitude increased during early adaptation only in the latter group. These findings collectively suggest that in the context of motor learning, the P3 ERP is associated with a need to develop, or adjust, a cognitive strategy.

Age-related differences in delta-beta phase-amplitude coupling in autistic individuals

ObjectiveWe aim to investigate the relationship between the core symptoms of autism, anxiety levels, and attention deficit hyperactivity disorder (ADHD) traits, and a non-autism-specific, neurophysiological metric, the Delta-Beta phase-amplitude coupling (PAC), extracted from the resting-state EEG for autistic and non-autistic populations across three different age groups (children, adolescents, and adults). MethodsWe analyze the eyes-open resting-state EEG of 371 individuals. We applied a phase de-biasing PAC algorithm expected to result in a more accurate PAC estimate than other PAC methodologies available in the literature. ResultsIn the adult group, we found a significant increase of the delta-beta PAC in the autistic subgroup who met the Autism Diagnostic Observation Schedule-2 (ADOS-2) Autism Diagnostic Interview-Revised (ADR-R) ADOS-2/ADI-R threshold compared to non-autistic individuals. The differences seem age-specific since we found no statistically significant differences in the children and adolescent populations. Moreover, we found a significant positive correlation with the restricted and repetitive behaviours score of the ADOS-2 diagnostic instrument and with ADHD hyperactivity/impulsivity in the entire autistic cohort. ConclusionsThe neurophysiological differences we found only in the autistic individuals that meet the thresholds also point out the need for future studies that look for autistic neurodiverse subgroups beyond age. SignificanceThe delta-beta debiasing PAC (dPAC) may potentially serve as a severity biomarker in the autistic population.

Neuromechanical proficiency in elite performance decision-making: An event-related potential (ERP) analysis

This research focuses intensively on the neural mechanisms of action selection responses in elite athletes during high-stakes decision-making. It emphasizes the neuromechanical dimensions of these processes, contrasting the responses of expert and novice players within a theoretical framework of neural information processing in high-performance contexts. Utilizing advanced EEG technologies, including event-related potential (ERP) analysis, the study captures a comprehensive view of both behavioral and neurophysiological data. The central aim is to unravel the intricate neural underpinnings that distinguish elite athletes in their decision-making strategies. Key findings highlight: (1) Enhanced accuracy and swifter reaction times in elite athletes during the action selection phase; (2) Significant neurophysiological differences, marked by pronounced N1 peak amplitudes with prolonged latencies, reduced P2 peak amplitudes with stable latencies, decreased P3 peak amplitudes with reduced latencies, and increased average PSW amplitudes. These discoveries significantly advance our understanding of the neural foundations of expert decision-making in high-performance sports. This study not only sheds light on the cognitive and neural dynamics of elite sports performance but also provides a foundation for developing training and performance enhancement techniques in various high-stakes domains.

Diminished vibration perception and greater pressure pain sensitivity are associated with worse knee osteoarthritis outcomes across sex and race

ObjectiveTo examine associations of vibration sensitivity and pressure pain sensitivity with knee osteoarthritis (OA) outcomes across sex and race, which may relate to known sex and race disparities in clinical outcomes. DesignData were from the 2013-2015 visit of the Johnston County Osteoarthritis Project. Exposures were vibration perception threshold (VPT) measured at the bilateral medial femoral condyle (MFC) and first metatarsophalangeal joint (MTP), and pressure pain threshold (PPT) measured at the bilateral upper trapezius. Outcomes were knee pain severity and presence of knee symptoms, radiographic knee OA, and symptomatic knee OA in each knee. Cross-sectional associations of the exposures with the outcomes were examined using logistic regression models, overall and separately by sex and race. ResultsIn the VPT and PPT analyses, 851 and 862 participants (mean age 71 years, 68% female, 33% Black, body mass index 31 kg/m2) and 1585 and 1660 knees were included, respectively. Higher VPT (lower vibration sensitivity) at the MFC and first MTP joint was associated with all outcomes. Lower PPT (greater pressure pain sensitivity) was associated with greater knee pain severity. Associations of VPT and PPT with all outcomes were similar among females and males and Black and White individuals. ConclusionsDiminished vibration perception and greater pressure pain sensitivity were cross-sectionally associated with worse knee OA outcomes. Despite differences in VPT and PPT among females and males and Black and White adults, associations with knee OA outcomes did not differ by sex or race, suggesting neurophysiological differences do not relate to established disparities.

Resting state neurophysiology of agonist–antagonist myoneural interface in persons with transtibial amputation

The agonist–antagonist myoneural interface (AMI) is an amputation surgery that preserves sensorimotor signaling mechanisms of the central-peripheral nervous systems. Our first neuroimaging study investigating AMI subjects conducted by Srinivasan et al. (2020) focused on task-based neural signatures, and showed evidence of proprioceptive feedback to the central nervous system. The study of resting state neural activity helps non-invasively characterize the neural patterns that prime task response. In this study on resting state functional magnetic resonance imaging in AMI subjects, we compared functional connectivity in patients with transtibial AMI (n = 12) and traditional (n = 7) amputations (TA). To test our hypothesis that we would find significant neurophysiological differences between AMI and TA subjects, we performed a whole-brain exploratory analysis to identify a seed region; namely, we conducted ANOVA, followed by t-test statistics to locate a seed in the salience network. Then, we implemented a seed-based connectivity analysis to gather cluster-level inferences contrasting our subject groups. We show evidence supporting our hypothesis that the AMI surgery induces functional network reorganization resulting in a neural configuration that significantly differs from the neural configuration after TA surgery. AMI subjects show significantly less coupling with regions functionally dedicated to selecting where to focus attention when it comes to salient stimuli. Our findings provide researchers and clinicians with a critical mechanistic understanding of the effect of AMI amputation on brain networks at rest, which has promising implications for improved neurorehabilitation and prosthetic control.

Study Protocol: Global Research Initiative on the Neurophysiology of Schizophrenia (GRINS) project

BackgroundObjective and quantifiable markers are crucial for developing novel therapeutics for mental disorders by 1) stratifying clinically similar patients with different underlying neurobiological deficits and 2) objectively tracking disease trajectory and treatment response. Schizophrenia is often confounded with other psychiatric disorders, especially bipolar disorder, if based on cross-sectional symptoms. Awake and sleep EEG have shown promise in identifying neurophysiological differences as biomarkers for schizophrenia. However, most previous studies, while useful, were conducted in European and American populations, had small sample sizes, and utilized varying analytic methods, limiting comprehensive analyses or generalizability to diverse human populations. Furthermore, the extent to which wake and sleep neurophysiology metrics correlate with each other and with symptom severity or cognitive impairment remains unresolved. Moreover, how these neurophysiological markers compare across psychiatric conditions is not well characterized. The utility of biomarkers in clinical trials and practice would be significantly advanced by well-powered transdiagnostic studies. The Global Research Initiative on the Neurophysiology of Schizophrenia (GRINS) project aims to address these questions through a large, multi-center cohort study involving East Asian populations. To promote transparency and reproducibility, we describe the protocol for the GRINS project.MethodsThe research procedure consists of an initial screening interview followed by three subsequent sessions: an introductory interview, an evaluation visit, and an overnight neurophysiological recording session. Data from multiple domains, including demographic and clinical characteristics, behavioral performance (cognitive tasks, motor sequence tasks), and neurophysiological metrics (both awake and sleep electroencephalography), are collected by research groups specialized in each domain.ConclusionPilot results from the GRINS project demonstrate the feasibility of this study protocol and highlight the importance of such research, as well as its potential to study a broader range of patients with psychiatric conditions. Through GRINS, we are generating a valuable dataset across multiple domains to identify neurophysiological markers of schizophrenia individually and in combination. By applying this protocol to related mental disorders often confounded with each other, we can gather information that offers insight into the neurophysiological characteristics and underlying mechanisms of these severe conditions, informing objective diagnosis, stratification for clinical research, and ultimately, the development of better-targeted treatment matching in the clinic.

The prediction potential indexes the meaning and communicative function of upcoming utterances

Prediction has a fundamental role in language processing. However, predictions can be made at different levels, and it is not always clear whether speech sounds, morphemes, words, meanings, or communicative functions are anticipated during dialogues. Previous studies reported specific brain signatures of communicative pragmatic function, in particular enhanced brain responses immediately after encountering an utterance used to request an object from a partner, but relatively smaller ones when the same utterance was used for naming the object. The present experiment now investigates whether similar neuropragmatic signatures emerge in recipients before the onset of upcoming utterances carrying different predictable communicative functions. Trials started with a context question and object pictures displayed on the screen, raising the participant's expectation that words from a specific semantic category (food or tool) would subsequently be used to either name or request one of the objects. Already 600 msec before utterance onset, a larger prediction potential was observed when a request was anticipated relative to naming expectation. As this result is congruent with the neurophysiological difference previously observed right after the critical utterance, the anticipatory brain activity may index predictions about the social-communicative function of upcoming utterances. In addition, we also found that the predictable semantic category of the upcoming word was likewise reflected in the anticipatory brain potential. Thus, the neurophysiological characteristics of the prediction potential can capture different types of upcoming linguistic information, including semantic and pragmatic aspects of an upcoming utterance and communicative action.

Обработка зрительной вербальной информации в условиях чтения и категоризации слов в составе одного согласованного словосочетания

The purpose of this study was to identify neurophysiological differences in information processing by the brain during passive reading and semantic categorization of individual words within a phrase. Materials and methods. The research involved 25 natural science students of Nizhny Novgorod universities. In the course of the experiment, the subjects were presented with word combinations consisting of an attribute and a noun on a computer monitor. In the first series of presentations, the task was to classify the attribute (target condition) and read the noun (non-target condition), in the second, to classify the noun and read the attribute. This allowed us to assess the restructuring of information processing when changing the task within a phrase, as well as to compare the processing of the word in the first and second positions in the target and non-target conditions. Using the 21-channel Neuron-Spectrum-4/VPM electroencephalograph (Neurosoft, Russia), event-related potentials (ERPs) obtained during the response to presented stimuli were recorded. Results. No differences were observed in attribute processing between the target and non-target conditions when tasks changed. For nouns, differences were revealed in ERP components between the target and non-target conditions. There was a more pronounced peak of the P200 component, a less pronounced peak of the N400 and a late negative wave of the N700 component during the categorization of nouns compared to their passive reading. Thus, when performing different tasks within a phrase, the brain changes the nature of verbal information processing, which is manifested in strengthening early lexical access, followed by the facilitation of lexico-semantic processing and activation of cognitive control mechanisms at the latest stages during the categorization of the second word in a phrase (noun) compared to its passive reading.

EEG spectral power in developmental coordination disorder and attention-deficit/hyperactivity disorder: a pilot study.

Developmental coordination disorder (DCD) and attention-deficit/hyperactivity disorder (ADHD) overlap in symptoms and often co-occur. Differentiation of DCD and ADHD is crucial for a better understanding of the conditions and targeted support. Measuring electrical brain activity with EEG may help to discern and better understand the conditions given that it can objectively capture changes and potential differences in brain activity related to externally measurable symptoms beneficial for targeted interventions. Therefore, a pilot study was conducted to exploratorily examine neurophysiological differences between adults with DCD and/or ADHD at rest. A total of N = 46 adults with DCD (n = 12), ADHD (n = 9), both DCD + ADHD (n = 8), or typical development (n = 17) completed 2 min of rest with eyes-closed and eyes-open while their EEG was recorded. Spectral power was calculated for frequency bands: delta (0.5-3 Hz), theta (3.5-7 Hz), alpha (7.5-12.5 Hz), beta (13-25 Hz), mu (8-13 Hz), gamma (low: 30-40 Hz; high: 40-50 Hz). Within-participants, spectral power in a majority of waveforms significantly increased from eyes-open to eyes-closed conditions. Groups differed significantly in occipital beta power during the eyes-open condition, driven by the DCD versus typically developing group comparison. However, other group comparisons reached only marginal significance, including whole brain alpha and mu power with eyes-open, and frontal beta and occipital high gamma power during eyes-closed. While no strong markers could be determined to differentiate DCD versus ADHD, we theorize that several patterns in beta activity were indicative of potential motor maintenance differences in DCD at rest. Therefore, larger studies comparing EEG spectral power may be useful to identify neurological mechanisms of DCD and continued differentiation of DCD and ADHD.

Age-related differences in long-term potentiation-like plasticity and short-latency afferent inhibition and their association with cognitive function

BackgroundThe neurophysiological differences in cortical plasticity and cholinergic system function due to ageing and their correlation with cognitive function remain poorly understood.AimsTo reveal the differences in long-term potentiation (LTP)-like plasticity...

Sex modulation of faces prediction error in the autistic brain

Recent research suggests that autistic females may have superior socio-cognitive abilities compared to autistic males, potentially contributing to underdiagnosis in females. However, it remains unclear whether these differences arise from distinct neurophysiological functioning in autistic males and females. This study addresses this question by presenting 41 autistic and 48 non-autistic adults with a spatially filtered faces oddball paradigm. Analysis of event-related potentials from scalp electroencephalography reveal a neurophysiological profile in autistic females that fell between those of autistic males and non-autistic females, highlighting sex differences in autism from the initial stages of face processing. This finding underscores the urgent need to explore neurophysiological sex differences in autism and encourages efforts toward a better comprehension of compensation mechanism and a clearer definition of what is meant by camouflaging.

Clinical and neurophysiological manifestations of sluggish cognitive tempo in children

To study the clinical and neurophysiological features of children with low cognitive tempo (NCT), as well as the effectiveness of the drug Pantogam in the treatment of this pathology. A total of 90 children aged 8 to 10 years were examined. Of these, the main study group consisted of 30 children with NCT, the comparison group consisted of 30 children with a combined type of attention deficit hyperactivity disorder ADHD (ADHD-K), the control group consisted of 30 children without neuropsychiatric disorders. The study used clinical, neurophysiological (electroencephalography (EEG)) and parametric methods. The CMAS scale of apparent anxiety (The Children's Form of Manifest Anxiety Scale), the SNAP-IY scale (assessment of the degree of inattention, hyperactivity and impulsivity), the TOVA computer test (the Test of Variables of Attention), the scale «SCT» (Sluggish Cognitive Tempo) for assessing manifestations of low cognitive tempo, the «RAM» technique for quantifying working memory. Pantogam was used to treat patients at a dose of 750 mg per day for 8 weeks. Patients with NCT are characterized by more pronounced attention disorders compared with healthy peers and with children with ADHD-K, and they have a decrease in mainly not selective attention, but the overall level of functional activity. Also, the group of children with NCT has an increased level of anxiety compared to the group of children with ADHD. A comparative analysis of the level of impulsivity showed that children with NCT are less characterized by a deficit in inhibition processes. According to the quantitative analysis of the EEG, specific changes in functional activity in the frontal and central regions of the cerebral cortex were revealed (a statistically significant increase in the ratio of absolute theta rhythm to beta1 rhythm, compared with other groups), reflecting insufficient cortical arousal and less focused neural states. When re-evaluating the condition of children with NCT after a course of therapy with Pantogam, an improvement in the form of a decrease in the degree of inattention, the severity of memory impairment and a decrease in reaction time was recorded in 60% of cases. According to quantitative EEG analysis, there was a significant decrease in the ratio of absolute theta rhythm to beta1 rhythm in the central leads of both hemispheres and in the parietal-temporal leads of the left hemisphere, indicating an increase in the level of overall activation of the cerebral cortex after a course of treatment. Clinical and neurophysiological differences were revealed in patients with NCT and with combined ADHD. It has been shown that the use of Pantogam for the treatment of children with NCT leads not only to a decrease in the main manifestations of this disorder, but also to an improvement in the functional state of the brain.

Limited clinical validity of univariate resting-state EEG markers for classifying seizure disorders.

Differentiating between epilepsy and psychogenic non-epileptic seizures presents a considerable challenge in clinical practice, resulting in frequent misdiagnosis, unnecessary treatment and long diagnostic delays. Quantitative markers extracted from resting-state EEG may reveal subtle neurophysiological differences that are diagnostically relevant. Two observational, retrospective diagnostic accuracy studies were performed to test the clinical validity of univariate resting-state EEG markers for the differential diagnosis of epilepsy and psychogenic non-epileptic seizures. Clinical EEG data were collected for 179 quasi-consecutive patients (age > 18) with a suspected diagnosis of epilepsy or psychogenic non-epileptic seizures who were medication-naïve at the time of EEG; 148 age- and gender-matched patients subsequently received a diagnosis from specialist clinicians and were included in the analyses. Study 1 is a hypothesis-driven study testing the ability of theta power and peak alpha frequency to classify people with epilepsy and people with psychogenic non-epileptic seizures, with an advanced machine learning pipeline. The next study (Study 2) is data-driven; a high number of quantitative EEG features are extracted and a similar machine learning approach as Study 1 assesses whether previously unexplored univariate EEG measures show promise as diagnostic markers. The results of Study 1 suggest that EEG markers that were previously identified as promising diagnostic indicators (i.e. theta power and peak alpha frequency) have limited clinical validity for the classification of epilepsy and psychogenic non-epileptic seizures (mean accuracy: 48%). The results of Study 2 indicate that identifying univariate markers that show good correlation with a categorical diagnostic label is challenging (mean accuracy: 45-60%). This is due to a considerable overlap in neurophysiological features between the diagnostic classes considered in this study, and to the presence of more dominant EEG dynamics such as alterations due to temporal proximity to epileptiform discharges. Markers that were identified in the context of previous epilepsy research using visually normal resting-state EEG were found to have limited clinical validity for the classification task of distinguishing between people with epilepsy and people with psychogenic non-epileptic seizures. A search for alternative diagnostic markers uncovered the challenges involved and generated recommendations for further research.

Bilateral Corticomotor Reorganization and Symptom Development in Response to Acute Unilateral Hamstring Pain: A Randomized, Controlled Study

Accumulating evidence demonstrates that pain induces adaptations in the corticomotor representations of affected muscles. However, previous work has primarily investigated the upper limb, with few studies examining corticomotor reorganization in response to lower limb pain. This is important to consider, given the significant functional, anatomical, and neurophysiological differences between upper and lower limb musculature. Previous work has also focused on unilateral corticomotor changes in response to muscle pain, despite an abundance of literature demonstrating that unilateral pain conditions are commonly associated with bilateral motor dysfunction. For the first time, this study investigated the effect of unilateral acute hamstring pain on bilateral corticomotor organization using transcranial magnetic stimulation (TMS) mapping. Corticomotor outcomes (TMS maps), pain, mechanical sensitivity (pressure pain thresholds), and function (maximal voluntary contractions) were recorded from 28 healthy participants at baseline. An injection of pain-inducing hypertonic (n = 14) or pain-free isotonic (n = 14) saline was then administered to the right hamstring muscle, and pain ratings were collected every 30 seconds until pain resolution. Follow-up measures were taken immediately following pain resolution and at 25, 50, and 75 minutes post-pain resolution. Unilateral acute hamstring pain induced bilateral symptom development and changes in corticomotor reorganization. Two patterns of reorganization were observed—corticomotor facilitation and corticomotor depression. Corticomotor facilitation was associated with increased mechanical sensitivity and decreased function bilaterally (all P < .05). These effects persisted for at least 75 minutes after pain resolution. PerspectiveThese findings suggest that individual patterns of corticomotor reorganization may contribute to ongoing functional deficits of either limb following acute unilateral lower limb pain. Further research is required to assess these adaptations and the possible long-term implications for rehabilitation and reinjury risk in cohorts with acute hamstring injury.

Acquisition and extinction of active avoidance compulsive-like behavior in mice

Approximately 90% of adults have ever experienced obsessions, yet less than 3% of them develop OCD. It is hypothesized that excessive fear of negative events contributes to OCD onset and development, which is related to the individual differences in psychopathology and neurophysiology associated with OCD among those who experience obsessions. To explore the hypothesis, this study examined if a fear-inducing aversive footshock could induce compulsive-like lever-pressing behavior in mice, the effects of extinction treatments on the compulsive-like behavior, and how the expression of tryptophan hydroxylase 2 (TPH2) in the amygdala would be regulated. This study successfully established a novel active avoidance OCD model in mice (model mice), manifesting compulsive-like lever-pressing with a smaller range of exploring in response to fear-inducing footshock. The compulsive-like behavior could be alleviated. The TPH2 in the left amygdala was down-regulated in model mice but up-regulated after food treatment and fluoxetine treatment. Food was the most effective treatment for reducing compulsive-like behavior and up-regulating the TPH2 levels in the left amygdala, followed by fluoxetine, sham, and sound. Our findings elucidate the fundamental processes of the acquisition and extinction of an active avoidance compulsive-like behavior in mice and provide insight into potential interventions to improve the prognosis of the compulsive-like behavior. This study provides evidence that the acquisition and extinction of active avoidance compulsive-like behavior in mice is associated with neuroplasticity relevant to protein regulation affected by brain-environment interactions.