Clinical EEG and neuroscience最新文献

Artifacts are a common occurrence during EEG recording and typically do not present a significant challenge to skilled neurophysiologists. However, in rare instances physiological electroencephalographic activity may closely mimic artifacts, potentially leading to missed or significantly delayed diagnosis. We report a case involving highly focal electrographic seizures initially recorded on a single electrode, posing a substantial diagnostic challenge. This delay in recognizing the seizures highlights the importance of careful EEG interpretation, especially in cases of unusual or subtle findings, to ensure timely diagnosis and treatment. We suggest using EEG arrays with a higher number of electrodes to improve spatial resolution or incorporating neuroimaging for correlation in such challenging cases.

IntroductionEpileptiform K complexes (eKC) and small sharp spikes (SSS) have been explored in a limited number of studies, with their relationhip to epileptic disorders remaining controversial. This retrospective study aimed to evaluate the significance of eKC and SSS in patients with epilepsy for clinical practice.MethodsAmong 370 consecutive patients over the age of 18, who underwent long-term video EEG monitoring, 63 were included based on having at least 20 min of recording after sleep onset and sufficient clinical data. eKC and SSS were visually analyzed by two investigators. Statistical comparisons were made between demographic and clinical data, EEG and neuroimaging features, prognostic evaluations of patients with and without eKC and SSS.ResultsAmong the 63 patients investigated, 38.1% exhibited eKC, and 14.3% showed SSS in their sleep recordings, with all affected individuals diagnosed with focal epilepsy syndromes. Compared to patients without eKCs, those with eKCs showed more frequent interictal bilateral slow waves during wakefulness (p = .045), and their ictal EEGs were less lateralized (p = .041). We found that eKCs were more likely to be detected with longer sleep analysis durations (p = .004). In the presence of SSS, ictal EEG was significantly more lateralized (p = .017) and associated with favorable surgical outcomes in patients who underwent epilepsy surgery (p = .015).ConclusionOur analysis highlight that eKC and SSS can be present in focal epilepsy syndromes. When considered as an epileptiform EEG phenomenon in drug-resistant epilepsy, these EEG findings may provide additional information during presurgical evaluation and SSS may help to predict surgical outcome.

Parkinson's disease (PD) is a progressive neurodegenerative disorder that profoundly affects patients' quality of life. Early and accurate diagnosis is essential for timely intervention and improved outcomes, yet traditional clinical evaluations often fall short. This review examines recent advancements in machine learning (ML) and deep learning (DL) techniques that promise more objective, quantitative, and precise PD diagnosis. By leveraging diverse data sources-including electroencephalogram (EEG) signals, voice recordings, and Magnetic Resonance Imaging (MRI) scans-these techniques offer a comprehensive approach to understanding and diagnosing PD. The review evaluates the effectiveness of specific ML and DL techniques applied to each data source and addresses existing challenges, such as the need for larger and more diverse datasets, model interpretability for clinical adoption, and generalizability across different healthcare settings. Additionally, it discusses promising future directions, including the potential of explainable AI models and multimodal data analysis, to further enhance PD diagnosis.

BackgroundThis study investigated whether P300, a component of event-related potentials (ERPs), and cognitive performance related to frontal lobe function can predict responsiveness to a brief cognitive behavioral intervention in individuals who consume alcohol on ≥3 days per week.MethodsParticipants were 35 habitual drinkers (drinking alcohol on ≥3 days per week). At baseline, they completed self-report questionnaires assessing alcohol consumption, neuropsychological tests reflecting frontal lobe function (eg, the Trail Making Test, Stroop Test, Digit Symbol Substitution Test, verbal fluency tests), and P300 assessment during a visual oddball task with alcohol-related images. All participants then received ∼30 min of structured counseling on drinking behavior, followed by a second brief intervention at 3 months. Alcohol intake was reported at both time points, and total daily alcohol consumption (in standard drinks) was calculated. Participants were categorized as successful reducers if their daily alcohol intake at three months was lower than at baseline (n = 27), and as unsuccessful if intake was unchanged or increased (n = 8). Baseline ERP and neuropsychological measures were compared between groups.ResultsParticipants who reduced their drinking had significantly lower P300 amplitudes at P3 and Fz at baseline compared with those who did not. No significant between-group differences were found in neuropsychological performance.ConclusionsLower P300 amplitudes may serve as a neurophysiological marker for predicting responsiveness to brief psychosocial interventions for alcohol reduction in individuals with high-risk drinking, potentially providing greater sensitivity than traditional neuropsychological tests.

Study ObjectivesVertex sharp waves(VSW) are sharply contoured waves with a duration of less than 500 mille-seconds and maximal over the central regions of the brain, that have been identified to appear during N1. Here we postulate that VSW are sleep stage-specific and can also identify a sleep stage shift to NREM sleep from REM sleep.MethodsWe retrospectively analyzed PSG data of 20 out of 74 consecutive patients who were studied with 18-channel EEG within the last year. Vertex sharp waves were visually and manually scored and analyzed by sleep stage.ResultsTwenty patients(12 men, 60.0%) were analyzed. The median age was 37 years(95% CI 31.3-46.2 years) with a mean of 38.7 ± 14.4 years. Seventeen patients(85%) had VSW in both N1 and N2 sleep stage, only 6 patients(30%) had VSW in N3 sleep, and 10 patients(50%) in REM sleep. Regression analysis showed that the occurrence of VSW in N2 sleep(r² = 0.747,F = 44.366;p < 0.001) and REM sleep(r² = 0.473,F = 7.174; p = 0.028) was positively correlated with the presence of VSW in N1 sleep stage. The positive correlation during REM sleep was only spared for the VSW appearing following an arousal reaction(r² = 0.432, F = 5.329;p = 0.05).ConclusionsOur results suggest that vertex sharp waves are state-dependent activities of NREM sleep, predominantly seen in N1 sleep stage, and also in N2 sleep. As they emerge in REM sleep, following an arousal reaction or not, it may be regarded as a sleep stage shift from REM to NREM sleep stage. These findings may help clarify scoring rules for REM sleep and arousal.

BackgroundPsychosocial stress-particularly bullying-has been recognized as a critical determinant of mental and neurophysiological health in children. Chronic stress exposure may disrupt cortical regulatory mechanisms detectable through quantitative electroencephalography (q-EEG).ObjectiveThis study examined the correlation between perceived psychological stress, involvement in bullying, and q-EEG spectral anomalies among Indonesian school-aged children, seeking to determine if bullying-related stress generates unique neurophysiological patterns or indicates a general dysregulation of stress responses.MethodsA two-phase design was implemented. Phase I included 2781 8-13-year-olds who completed the PSS-10 and a validated bullying questionnaire. Using a Mitsar-EEG 201 equipment, Phase II selected 24 students with increased stress levels (PSS ≥ 27) for q-EEG examination. Electroencephalogram signals from 19 scalp sites were converted into z-scores using age-adjusted NeuroGuide database standards. Stress level and brain activity were correlated using Spearman's rho.ResultsThe majority of subjects (23 out of 25; 95.8%) had EEG activity above ±2 standard deviations, especially in the temporal and prefrontal areas. There was a negative correlation between stress and temporal alpha power (r = -0.43, p = 0.028) and a positive correlation between stress with enhanced prefrontal high-beta power (r = 0.47, p = 0.021). Neurophysiological alterations among bullied children closely paralleled those under non-bullying stressors such as academic overload or family conflict.ConclusionElevated stress intensity, regardless of its psychosocial origin, was associated with convergent cortical dysregulation patterns. These results suggest that q-EEG may be a viable non-invasive method for early stress-related neurophysiological dysfunction diagnosis and that pediatric populations require integrated emotional regulation therapies.

BackgroundAssessment and treatment monitoring in alcohol dependence syndrome often rely on subjective measures, particularly in resource-limited settings. Quantitative electroencephalogram (qEEG) provides an objective alternative, though its role in alcohol use and abstinence remains underexplored in the Indian context.AimTo study changes in the quantitative electroencephalogram in persons with alcohol dependence syndrome undergoing treatment.MethodsPatients diagnosed with alcohol dependence syndrome as per ICD-11 were recruited. At baseline, the Severity of Alcohol Dependence Questionnaire (SADQ) (mean 22.60 ± 4.81) and Clinical Institute Withdrawal Assessment for Alcohol-Revised (CIWA-Ar) (mean 10.98 ± 2.45) were administered to assess the severity of dependence and withdrawal symptoms. qEEG was recorded at baseline, following detoxification and at 12 weeks. Detoxification was done using benzodiazepines via a symptom-triggered regimen. Baclofen was offered post-detoxification with regular follow-ups. EEG signals were analysed for changes across standard frequency bands in various scalp regions and in terms of absolute powers.ResultsSixty patients completed the 12-week follow-up. The sample consisted of all males, with a mean age of 40.85 ± 8.30 years. Alpha and gamma powers showed increasing trends, while beta, theta, and delta powers declined across most scalp regions. Absolute power trends were similar, with a statistically significant reduction noted in the delta wave (p-value=.024). No significant correlation was found between severity of dependence and wave powers, except for gamma in the fronto-parietal region (p-value=.01) and beta in the central region (p-value=.021).ConclusionqEEG changes with detoxification and abstinence may serve as an objective indicator for assessing treatment efficacy and abstinence status in alcohol dependence.

To investigate the relationship between age-related brain volume loss and neural functional connectivity (FC), whole brain volume and mean FC were calculated in 75 healthy participants aged 20 to 86 years (39 women, 36 men; mean age: 59.31 years). Resting-state MEG with eyes closed and MRI were conducted. Correlations between age and whole brain volume, mean neural connectivity expressed as amplitude envelope correlation (AEC) in the alpha frequency band across 66 functional parcellations, and the standard deviation (SD) of AEC were analyzed. In seven brain regions showing significant age-related volume loss, mean AEC and SD of AEC with other regions were assessed. Whole brain volume decreased with age (r = -0.322, p = .00480), particularly in participants older than 75 years (p < .05, ANOVA). AEC values also declined with age (r = -0.359, p = .00153), with significant differences observed between generational subgroups under 45 and over 75 years (p < .05). The SD of AEC decreased across the brain with age (r = -0.326, p = .0043). However, seven brain regions with significant age-related volume loss did not consistently show significant differences in AEC or its SD between generational subgroups, in contrast to consistent volume differences observed. Overall, brain volume and neural FC declined with age, accompanied by reduced variability in FC across the brain. Nevertheless, regions exhibiting significant volume loss were not always associated with functional decline in FC or its variability, suggesting the brain may compensate for global decline through localized functional adaptations.

Breach rhythm (BR) is a well-recognized EEG pattern characterized by high-amplitude, sharply contoured fast activity over areas of skull defect, most often following craniotomy or trauma. Although considered physiological, BR may closely mimic epileptiform discharges, leading to diagnostic uncertainty. We report a 33-year-old man with bilateral skull defects secondary to traumatic brain injury who presented with recurrent generalized tonic-clonic seizures. EEG showed continuous fast and sharp activity over the right F4-C4 region, consistent with BR, and diffuse slow waves over the left hemisphere. During two focal seizures, ictal discharges originating from the right F8 electrode transiently modified the morphology and rhythmicity of the ongoing BR before spreading bilaterally. Interestingly, no BR was observed over the left hemisphere despite a large skull defect, likely reflecting severe cortical injury. Following treatment with levetiracetam and phenytoin, seizures resolved, while the right-sided BR persisted unchanged. This case highlights that BR is not merely a passive artifact of altered conductivity but a dynamic indicator of cortical function. Its modulation during seizures and absence over structurally damaged cortex support the concept that BR may serve as a potential marker of cortical viability. Recognizing these patterns may prevent misinterpretation of physiological BR as epileptiform activity and enhance EEG evaluation in patients with structural brain lesions.