Electroencephalographic Patterns Research Articles

Clinical phenotype and functional influence of GRIN2A variants in epilepsy-aphasia syndrome.

N-methyl-D-aspartate receptors are glutamate-gated ion channels that play a crucial role in brain function. Numerous inherited or de novo variants in the GRIN2A gene, encoding the GluN2A subunit of the receptor, have been identified in patients with epilepsy. In addition, it is worth noting that GRIN2A variants exhibit a strong correlation with epilepsy-aphasia syndromes, a group of age-dependent epileptic, cognitive, and language disorders with a characteristic electroencephalographic pattern. Whole exome sequencing was conducted in enrolled patients with epilepsy-aphasia syndromes, and GRIN2A variants were screened. The conservation of substituted residues, conformational changes of mutant subunits, and in silico predictions of pathogenicity were thoroughly assessed in our study. Functional alterations of the variants were examined using whole-cell voltage-clamp current recordings while the relative surface expression levels of subunit proteins were assessed via immunofluorescence assays. A summary of previously published GRIN2A missense variants was conducted to investigate the genotypic-phenotypic-functional correlations. Two missense GRIN2A variants (c. 2482A >G/p. M828V, c.2627 T >C/p. I876T) were identified, which are located in the transmembrane helix M4 and C-terminus domain of the GluN2A subunit, respectively. Both variants exhibited reduced current density of NMDARs and surface/total expression levels of GluN2A subunits, while M828V showed a decreased extent of desensitization as well. A further summary of the previously reported GRIN2A variants demonstrated that more variable phenotypes were observed for variants situated in the C-terminus domain or those with loss-of-function effects. Our study expands the phenotypic and functional range of GRIN2A-related disorders. In order to optimally establish the domain-function-phenotype correlations in GRIN2A variants, it is imperative to gather a more extensive set of clinical and functional data. This study has identified two genetic variants of the GRIN2A gene in patients with epilepsy-aphasia syndrome. We assess the variants' harmfulness through a variety of functional experiments, including evaluating the expression level of the mutated protein and the resulting changes in electrophysiological activities. Also, we reviewed previously published papers about GRIN2A variants in epilepsy to learn more about the correlations between their locations, functional changes, and clinical manifestations.

Clinical and Radiological Parameters Affecting the Yield of Routine Electroencephalography in Various Indications.

To highlight the significance of various clinical and radiological parameters in association with specific electroencephalographic (EEG) patterns in order to prioritize EEG referrals. This retrospective, cross-sectional study was conducted in the neurology department of King Fahad University Hospital, Alkhobar, and involved a review and analysis of EEG and medical records pertaining to 604 patients referred for routine EEG. The data were analyzed using SPSS version 22. An association between various parameters and EEG yield was established. Factors associated with the yield of abnormal EEG patterns were diverse, like generalized tonic-clonic seizures (GTCs) (P =.05), status epilepticus (SE) (P =.05), altered level of consciousness (ALC) (P =.00), abnormal movement (P =.00), cardiac arrest (P =.00), prior history of epilepsy (P =.04), chronic renal disease (CRD) (P =.03), abnormal neurological exam (P =.00), and cortical lesions on brain imaging (P =.00). Among the abnormal EEG patterns, epileptiform activity (EA) in EEG was associated with focal seizures (P =.03), GTCs (P =.00), falls (P =.05), cardiac arrest (P =.00), a history of epilepsy (P =.00), and hypoxic ischemic injury (P =.03). Encephalopathy in EEG was also associated with focal sz (P =.02), GTCs (P =.00), SE (P =.01), ALC (P =.00), cardiac arrest (P =.00), history of stroke (P =.01), and epilepsy (P =.00). Among the studied parameters, patient level of consciousness, neurological exam findings, and neuroimaging findings, with some discrepancies, were found to be the most consistent in predicting the EEG yield. The study demonstrated the value of a proper neurological exam and careful selection of patients to gain the optimum benefit from the routine EEG.

Exposure to nicotine and withdrawal in Wistar rats: an electrophysiological study.

Throughout the world, smoking is one of the principal causes of preventable death. Nicotine, the primary active component of tabacco, acts as a psychostimulant and modulates the electrical activity of a number of the areas of the brain involved in addiction. Abstinence from nicotine will also impact the functional state of the brain, which is reflected in symptoms of craving and susceptibility to relapse. In addition, given the increase in the sympathetic tone of the heart and pulse rate promoted by nicotine, its consumption can contribute to tachyarrhythmia. The present study investigated the electroencephalographic (EEG) and electrocardiographic (ECG) patterns of Wistar rats submitted to acute or chronic exposure to nicotine, followed by withdrawal for 24 or 48 hours, and the re-administration (or not) of nicotine, to simulate episodes of relapse. The EEG data revealed an increase in all types of brainwaves, with emphasis on high-frequency (alpha, beta, and gamma) brain oscillations following both acute and chronic exposure to nicotine (14 days), whereas in withdrawal, there was a predominancy of delta waves. When exposure to nicotine was reinstated after withdrawal, the observed EEG profile was similar to that found in chronic exposure. The electrocardiogram reads showed that both acute and chronic exposure to nicotine caused abnormalities in the atrioventricular conduction and that, while these changes improve with substance withdrawal, relapse can worsen these parameters. The results of this study indicate that high-frequency brainwaves are correlated with nicotine dependence, while slow brain oscillations are consistent with drug craving, and episodes of nicotine relapse can reproduce brain activity patterns linked to dependence. Finally, exposure to nicotine predisposes the individual to heart rhythm abnormalities, which are attenuated by withdrawal, but may nevertheless be restored rapidly with re-exposure to the substance. This study demonstrated that nicotine increases high-frequency brain oscillations, which is associated with addiction, whereas withdrawal elevates the delta wave power, suggesting craving. Re-exposure to nicotine following withdrawal restores rapidly the EEG profile of chronic dependence. In addition, nicotine has deleterious impacts on cardiac activity, which are linked to fatal arrhythmias. This implies that stopping smoking is beneficial for the amelioration of the alterations in heart rhythm caused by nicotine addiction. This study elucidates the functional states of the brain and heart during both sporadic and chronic nicotine use, and the electrophysiological explanation for substance dependence and drug relapse after craving episodes.

Electroencephalogram and phenotype patterns in neuronopathic Gaucher disease patients – ten years of experience in a single center

BackgroundThis study aimed to investigate the unique electroencephalography (EEG) patterns in neuronopathic Gaucher disease (GD) patients and explore the correlations between EEG findings and neurological phenotypes so as to optimize clinical outcomes.MethodsA retrospective analysis was conducted on 74 EEG recordings from 50 GD patients between January 2012 and July 2022.ResultsTwenty-three patients exhibited abnormal EEG recordings, including 11 of the GD1 type (the transitional type) and 12 with neuronopathic GD. Of the 12 neuronopathic GD patients, 9 patients with epilepsy were analysed specifically in terms of the clinical course. The primary waveform observed in the neuronopathic EEG recordings was the spike-and-wave complex (SWC) during both awake and sleep states. This was significantly different from sharp waves observed only during sleep in the patients of the transitional type (P = 0.0230). The abnormal discharges in the neuronopathic patients were most commonly located in the bilateral Rolandic areas, while the transitional type commonly involved the bilateral frontal regions. Three patients with an epileptic EEG pattern reported their initial seizures years later. Seizures in the neuronopathic patients were effectively controlled with anti-seizure medications (ASMs), despite the ongoing presence of abnormal EEG patterns. The EEG patterns during ocular symptoms were characterized by sporadic or continuous unilateral SWC during sleep.ConclusionsPatients with neuronopathic GD exhibit distinct EEG patterns that can help differentiate them from GD1 patients. Early treatment with ASMs can effectively control seizures. EEG plays a crucial role in monitoring seizures and can facilitate prompt intervention for GD patients.

The Relative Impact of Clinical and Investigational Factors to Predict the Outcome in Stroke Patients.

As stroke is still considered a significant cause of mortality and morbidity, it is crucial to find the factors affecting the outcome in these patients. We aimed to interpret the various clinical and investigational parameters and establish their association with the outcome in stroke patients. This is a retrospective, cross-sectional study, conducted in the Department of Neurology between June 2019 to November 2021. The study involved the review and analysis of medical records pertaining to 264 patients, admitted with the diagnosis of stroke. Various clinical, radiological, and electroencephalographic (EEG) patterns in stroke patients were analyzed and their association with outcome was established. The association between the studied variables was performed by the logistic regression (LR) and presented as odds ratio (OR) and 95% confidence interval (CI). The study sample consisted of 264 patients. Males comprised 165 (62.5%) with the mean participant age of 57.17 ± 18.7 3 years (range: 18-94). Patients younger than 50 years had a better likelihood of a good outcome in comparison to patients older than 50. The admission location was the most significant factor in predicting the outcome ( P = 0.00) in favor of inpatient department and outpatient department (OPD), in contrast to patients admitted directly to intensive care unit (ICU). Normal EEG was associated with good outcome ( P = 0.04; OR, 3.3; CI, 1.01-10.88) even after adjustment of the confounders, whereas patients having marked EEG slowing had a poor outcome ( P = 0.05; OR, 2.4; CI, 0.65-8.79). Among the clinical parameters, hemiparesis ( P = 0.03), trauma ( P = 0.01), generalized tonic-clonic seizures (GTC) ( P = 0.00), and National Institutes of Health Stroke Scale of more than 4 were more likely associated with a poor outcome as well as the presence of intracranial hemorrhage (ICH) or infarction in the cortical and cortical/subcortical locations were associated with poor outcomes. After adjustment of confounders, the factors found to have prognostic significance in favor of good outcomes were inpatients or OPD referrals and normal EEG while direct admission to ICU, marked slowing on EEG, and presence of ICH were found to be associated with poor outcome. Certain patterns are predictive of good or worse outcomes in stroke patients. Early identification of these factors can lead to early intervention, which in turn might help in a better outcome. The results of the study, therefore, have some prognostic significance.

Bilateral centromedian nucleus of thalamus responsive neurostimulation for pediatric-onset drug-resistant epilepsy.

Neuromodulation therapies offer an efficacious treatment alternative for patients with drug-resistant epilepsy (DRE), particularly those unlikely to benefit from surgical resection. Here we present our retrospective single-center case series of patients with pediatric-onset DRE who underwent responsive neurostimulation (RNS) depth electrode implantation targeting the bilateral centromedian nucleus (CM) of the thalamus between October 2020 and October 2022. Sixteen patients were identified; seizure outcomes, programming parameters, and complications at follow-up were reviewed. The median age at implantation was 13 years (range 3.6-22). Six patients (38%) were younger than 12 years of age at the time of implantation. Ictal electroencephalography (EEG) patterns during patients' most disabling seizures were reliably detected. Ten patients (62%) achieved 50% or greater reduction in seizure frequency at a median 1.3 years (range 0.6-2.6) of follow-up. Eight patients (50%) experienced sensorimotor side effects, and three patients (19%) had superficial pocket infection, prompting the removal of the RNS device. Side effects of stimulation were experienced mostly in monopolar-cathodal configuration and alleviated with programming change to bipolar configuration or low-frequency stimulation. Closed-loop neurostimulation using RNS targeting bilateral CM is a feasible and useful therapy for patients with pediatric-onset DRE.

Efficacy and Safety of Vagus Nerve Stimulation in Lennox-Gastaut Syndrome: A Scoping Review.

Lennox-Gastaut syndrome (LGS) is a severe developmental and epileptic encephalopathy characterized by drug-resistant seizures, cognitive impairments, and abnormal electroencephalographic patterns. Vagus nerve stimulation (VNS) is a widely used neuromodulation therapy for LGS, but its effects on seizure outcomes, different seizure types, non-seizure outcomes, and adverse events in this population have not been comprehensively reviewed. To conduct a scoping review on the use of VNS in LGS, a literature search was performed in PubMed, OVID, Web of Science, and Embase from inception to 9 June 2024, using relevant keywords and without restrictions on study design. The search yielded forty eligible studies (twenty-four retrospective cohorts, fourteen prospective cohorts, and two registry analyses) comprising 1400 LGS patients treated with VNS. No randomized controlled trials were identified. Across studies, the median seizure reduction ranged from 20.6% to 65%, with 0% to 100% of patients achieving a ≥50% seizure reduction. No consistent preoperative biomarker of VNS responsiveness was identified in LGS. Although inconsistent among different studies, tonic, atonic, and tonic-clonic seizures responded best, while focal seizures responded worst. Improvements in seizure severity, alertness, and quality of life were reported in some studies, but cognitive and adaptive functioning generally remained unchanged. Adverse events were mostly mild and transient, including hoarseness, cough, and paresthesia. Device-related complications and infections were uncommon. In conclusion, further research is needed to better understand VNS's position in the evolving LGS treatment landscape and its cost effectiveness.

A machine learning approach for differentiating bipolar disorder type II and borderline personality disorder using electroencephalography and cognitive abnormalities.

This study addresses the challenge of differentiating between bipolar disorder II (BD II) and borderline personality disorder (BPD), which is complicated by overlapping symptoms. To overcome this, a multimodal machine learning approach was employed, incorporating both electroencephalography (EEG) patterns and cognitive abnormalities for enhanced classification. Data were collected from 45 participants, including 20 with BD II and 25 with BPD. Analysis involved utilizing EEG signals and cognitive tests, specifically the Wisconsin Card Sorting Test and Integrated Cognitive Assessment. The k-nearest neighbors (KNN) algorithm achieved a balanced accuracy of 93%, with EEG features proving to be crucial, while cognitive features had a lesser impact. Despite the strengths, such as diverse model usage, it's important to note limitations, including a small sample size and reliance on DSM diagnoses. The study suggests that future research should explore multimodal data integration and employ advanced techniques to improve classification accuracy and gain a better understanding of the neurobiological distinctions between BD II and BPD.

Perampanel as an Add-On Therapy in Patients with Refractory Status Epilepticus and Postanoxic Encephalopathy: A Real-Life Single-Center Retrospective Cohort Study.

Data on the efficacy of perampanel in refractory status epilepticus (RSE) and postanoxic encephalopathy (PAE) are limited; its use in such conditions is currently off-label. We conducted a retrospective cohort study of consecutive adult patients with RSE, including PAE, exhibiting electroencephalographic patterns indicative of status epilepticus who were treated at our center (January 2018 to December 2022) with assessment of clinical and electroencephalographic outcomes. Thirty-six patients were included in the study, of whom 29 had nonanoxic RSE and 7 had PAE. Within the nonanoxic RSE subgroup, 45% (13 of 29; 95% confidence interval [CI] 27-63%) of study participants were responders, 34% (10 of 29; 95% CI 17-52%) were partial responders, and 21% (6 of 29; 95% CI 6-35%) were nonresponders. In the PAE subgroup (n = 7), no patients fully responded to perampanel; 43% (3 of 7; 95% CI 6-80%) were partial responders, and 57% (4 of 7; 95% CI 20-95%) were nonresponders. Responder and nonresponder study participants exhibited overlapping baseline characteristics. No significant differences in duration of hospitalization were observed between responders and nonresponders in both subgroups. Responders in the RSE subgroup had a median discharge modified Rankin Scale score of 3 (interquartile range 3-4), and nonresponders had a median discharge modified Rankin Scale score of 5 (interquartile range 5-6). Despite limitations from the retrospective design and the small population size, this study suggests that perampanel use in nonanoxic RSE appears to yield promising results at moderate doses, including a tendency toward a better functional outcome at discharge, without significant adverse effects. However, in patients with PAE, the drug seems to show suboptimal performance. Perampanel appears to have promising efficacy as an add-on therapy in nonanoxic RSE. However, in patients with PAE, its efficacy seems to be lower. Further studies are warranted to confirm these observations.

Alteration in neural oscillatory activity and phase‐amplitude coupling after sleep deprivation: Evidence for impairment and compensation effects

SummaryInsufficient sleep can significantly affect vigilance and increase slow‐wave electroencephalographic power as homeostatic sleep pressure accumulates. Phase‐amplitude coupling is involved in regulating the spatiotemporal integration of physiological processes. This study aimed to examine the functional associations of resting‐state electroencephalographic power and delta/theta‐gamma phase‐amplitude coupling from the prefrontal cortex (PFC) to posterior regions with vigilance performance after sleep deprivation. Forty‐six healthy adults underwent 24‐hr sleep deprivation with resting‐state electroencephalographic recordings, and vigilant attention was measured using the Psychomotor Vigilance Task. Power spectral and phase‐amplitude coupling analyses were conducted, and correlation analysis was utilized to reveal the relationship between electroencephalographic patterns and changes in vigilance resulting from sleep deprivation. Sleep deprivation significantly declined vigilance performance, accompanied by increased resting‐state electroencephalographic power in all bands and delta/theta‐gamma phase‐amplitude coupling. The increased theta activity in centro‐parieto‐occipital areas significantly correlated with decreased mean and slowest response speed. Conversely, the increased delta‐low gamma and theta‐high gamma phase‐amplitude couplings negatively correlated with the deceleration of the fastest Psychomotor Vigilance Task reaction times. These findings suggest that sleep deprivation affects vigilance by altering electroencephalographic spectral power and information communication across frequency bands in different brain regions. The distinct effects of increased theta power and delta/theta‐gamma phase‐amplitude coupling might reflect the impairment and compensation of sleep deprivation on vigilance performance, respectively.

The dynamics of cyclic‐periodic phenomena during non‐rapid and rapid eye movement sleep

SummarySleep is a complex physiological state characterized by distinct stages, each exhibiting unique electroencephalographic patterns and physiological phenomena. Sleep research has unveiled the presence of intricate cyclic‐periodic phenomena during both non‐rapid eye movement and rapid eye movement sleep stages. These phenomena encompass a spectrum of rhythmic oscillations and periodic events, including cyclic alternating pattern, periodic leg movements during sleep, respiratory‐related events such as apneas, and heart rate variability. This narrative review synthesizes empirical findings and theoretical frameworks to elucidate the dynamics, interplay and implications of cyclic‐periodic phenomena within the context of sleep physiology. Furthermore, it invokes the clinical relevance of these phenomena in the diagnosis and management of sleep disorders.

Linking Dementia Pathology and Alteration in Brain Activation to Complex Daily Functional Decline During the Preclinical Dementia Stages: Protocol for a Prospective Observational Cohort Study.

Progressive difficulty in performing everyday functional activities is a key diagnostic feature of dementia syndromes. However, not much is known about the neural signature of functional decline, particularly during the very early stages of dementia. Early intervention before overt impairment is observed offers the best hope of reducing the burdens of Alzheimer disease (AD) and other dementias. However, to justify early intervention, those at risk need to be detected earlier and more accurately. The decline in complex daily function (CdF) such as managing medications has been reported to precede impairment in basic activities of daily living (eg, eating and dressing). Our goal is to establish the neural signature of decline in CdF during the preclinical dementia period. Gait is central to many CdF and community-based activities. Hence, to elucidate the neural signature of CdF, we validated a novel electroencephalographic approach to measuring gait-related brain activation while participants perform complex gait-based functional tasks. We hypothesize that dementia-related pathology during the preclinical period activates a unique gait-related electroencephalographic (grEEG) pattern that predicts a subsequent decline in CdF. We provide preliminary findings showing that older adults reporting CdF limitations can be characterized by a unique gait-related neural signature: weaker sensorimotor and stronger motor control activation. This subsample also had smaller brain volume and white matter hyperintensities in regions affected early by dementia and engaged in less physical exercise. We propose a prospective observational cohort study in cognitively unimpaired older adults with and without subclinical AD (plasma amyloid-β) and vascular (white matter hyperintensities) pathologies. We aim to (1) establish the unique grEEG activation as the neural signature and predictor of decline in CdF during the preclinical dementia period; (2) determine associations between dementia-related pathologies and incidence of the neural signature of CdF; and (3) establish associations between a dementia risk factor, physical inactivity, and the neural signature of CdF. By establishing the clinical relevance and biological basis of the neural signature of CdF decline, we aim to improve prediction during the preclinical stages of ADs and other dementias. Our approach has important research and translational implications because grEEG protocols are relatively inexpensive and portable, and predicting CdF decline may have real-world benefits. DERR1-10.2196/56726.

Epilepsy, EEG and chromosomal rearrangements.

Chromosomal abnormalities are associated with a broad spectrum of clinical manifestations, one of the more commonly observed of which is epilepsy. The frequency, severity, and type of epileptic seizures vary according to the macro- and microrearrangements present. Even within a single chromosomal anomaly, we most often deal with a phenotypic spectrum. The aim of the study was to look for chromosomal rearrangements with a characteristic electroencephalographic pattern. Only a few disorders have peculiar electroclinical abnormalities: 1p36, 4p16, 6q terminal or trisomy 12p, Angelman syndrome, inv dup 15, 15q13.3 deletions, ring 20, Down syndrome, or Xp11.22-11.23 duplication. We also reviewed studies on epileptic seizures and typical electroencephalographic patterns described in certain chromosomal rearrangements, focusing on the quest for potential electroclinical biomarkers. The comprehensive review concludes with clinical presentations of the most common micro and macro chromosomal rearrangements, such as 17q21.31 microdeletion, 6q terminal deletion, 15q inv dup syndrome, 2q24.4 deletion, Xp11.22-11.23 duplication, 15q13.3 microdeletion, 1p36 terminal deletion, 5q14.3 microdeletion, and Xq28 duplication. The papers reviewed did not identify any specific interictal electroencephalographic patterns that were unique and significant biomarkers for a given chromosomal microrearrangement. The types of seizures described varied, with both generalized and focal seizures of various morphologies being reported. Patients with chromosomal anomalies may also meet the criteria for specific epileptic syndromes such as Infantile Epilepsy Spasms Syndrome (IESS, West syndrome): 16p13.11, 15q13.3 and 17q21.31 microdeletions, 5q inv dup. syndrome; Dravet syndrome (2q24.4 deletion), Lennox-Gastaut syndrome (15q11 duplication. 1q13.3, 5q inv dup.); or Self-Limited Epilepsy with Autonomic Features (SeLEAS, Panayiotopoulos syndrome: terminal deletion of 6q.n), Self-Limited Epilepsy with Centrotemporal Spikes (SeLECT): fragile X syndrome. It is essential to better characterize groups of patients to more accurately define patterns of epilepsy and EEG abnormalities. This could lead to new treatment strategies. Future research is required to better understand epileptic syndromes and chromosomal rearrangements. PLAIN LANGUAGE SUMMARY: This paper presents EEG recording abnormalities in patients with various gene abnormalities that can cause epilepsy. The authors summarize these EEG variations based on a literature review to see if they occur frequently enough in other chromosomal abnormalities (in addition to those already known) to be a clue for further diagnosis.

A multicenter, randomized, doubleblind, placebo-controlled trial of amantadine to stimulate awakening in comatose patients resuscitated from cardiac arrest.

We hypothesized that the administration of amantadine would increase awakening of comatose patients resuscitated from cardiac arrest. We performed a prospective, randomized, controlled pilot trial, randomizing subjects to amantadine 100 mg twice daily or placebo for up to 7 days. The study drug was administered between 72 and 120 hours after resuscitation and patients with absent N20 cortical responses, early cerebral edema, or ongoing malignant electroencephalography patterns were excluded. Our primary outcome was awakening, defined as following two-step commands, within 28 days of cardiac arrest. Secondary outcomes included length of stay, awakening, time to awakening, and neurologic outcome measured by Cerebral Performance Category at hospital discharge. We compared the proportion of subjects awakening and hospital survival using Fisher exact tests and time to awakening and hospital length of stay using Wilcoxon rank sum tests. After 2 years, we stopped the study due to slow enrollment and lapse of funding. We enrolled 14 subjects (12% of goal enrollment), seven in the amantadine group and seven in the placebo group. The proportion of patients who awakened within 28 days after cardiac arrest did not differ between amantadine (n=2, 28.6%) and placebo groups (n=3, 42.9%; P>0.99). There were no differences in secondary outcomes. Study medication was stopped in three subjects (21.4%). Adverse events included a recurrence of seizures (n=2; 14.3%), both of which occurred in the placebo group. We could not determine the effect of amantadine on awakening in comatose survivors of cardiac arrest due to small sample size.

Electroencephalographic Patterns on Follow-Up Visits in Extremely Premature Infants With Periventricular Leukomalacia: An Observational Study

BackgroundPeriventricular leukomalacia (PVL) is a common brain injury in premature infants, and epilepsy remains a significant complication. One concerning electroencephalographic (EEG) pattern found is developmental and/or epileptic encephalopathy with spike-and-wave activation in sleep (DEE-SWAS). This pattern is associated with persistent neuropsychological and motor deficits, even without a diagnosis of epilepsy. The purpose of this study is to identify the relationships between various PVL grades and EEG patterns in this population on follow-up visits, especially the occurrence of DEE-SWAS pattern on EEG. MethodsThis is a retrospective study of <36 weeks gestational age newborns who were followed in the neurodevelopmental clinic at Corewell Health East/Corewell Health Children's Hospital in Royal Oak, Michigan, between 2020 and 2022. Patients' demographics along with prematurity complications, diagnostic head ultrasound (HUS), and EEG studies were reviewed and graded. EEG studies are usually ordered when seizures were suspected. ResultsA total of 155 newborns met the inclusion criteria. Twenty-six patients had PVL. Nine patients had grade 2 to 3 PVL based on HUS review. EEG was performed on 15 patients with PVL at a mean age of 22 months. More severe PVL grades were significantly associated with worse EEG patterns (P = 0.005). Five patients had DEE-SWAS pattern on EEG, all of whom had grade 2 or 3 PVL. Epilepsy was eventually diagnosed in three infants with PVL. ConclusionsEEG can help identify important abnormal electrographic patterns in premature infants with PVL early in life; this might give a window of opportunity to intervene early and improve long-term developmental outcomes in this population.

Extreme Delta Brush Electroencephalography Pattern in Anti-yo Encephalitis: A Case Report

Autoimmune encephalitis is complex and gradually being recognized. Anti-N-methyl-D-aspartate Receptor (Anti-NMDAR) encephalitis was the most well-known and its unique electroencephalography (EEG) pattern is extreme delta brush (EDB). Anti-Yo encephalitits is far less than common anti-NMDAR encephalitis (anti-NMDARE). A 78-year-old male presented with progressive apathy, hypotension, unsteady gait, and depressed consciousness. EEG revealed an EDB pattern while the serum test was positive for anti-Yo antibodies. The patient then received 10 rounds of plasma exchange, and his blood pressure stability improved. Consequently, urine cytology and abdominal computed tomography revealed atypical cells and linear enhancement in the bladder dome, respectively. However, instead of further pathological confirmation and treatment, the patient’s family requested hospice care. As a result, the patient died of desaturation 7 days later after the withdrawal of ventilatory support. First recognized in 2012, EDB is believed to be specific to NMDARE. However, to date, EDB has not been well described, and no description is available regarding its reactivity. To our knowledge, this is the first case of EDB with anti-Yo encephalitis. Similar to the cases of EDB with anti-NMDARE, our patient did not have satisfied prognosis despite no further investigation and treatment of the possible underlying malignancy. As the prevalence and underlying mechanism of this EEG pattern are unclear, further studies are warranted to identify the potentially similar mechanisms and correlation between anti-NMDAR and anti-Yo encephalitis.

Generalized Periodic Discharges Associated With Catatonia and Delirium: A Case Series.

Generalized periodic discharges are a repeated and generalized electroencephalography (EEG) pattern that can be seen in the context of altered mental status. This article describes a series of five individuals with generalized periodic discharges who demonstrated signs and symptoms of catatonia, a treatable neuropsychiatric condition. Inpatients with a clinical diagnosis of catatonia, determined with the Bush-Francis Catatonia Rating Scale (BFCRS), and EEG recordings with generalized periodic discharges were analyzed in a retrospective case series. Five patients with catatonia and generalized periodic discharges on EEG were evaluated from among 106 patients with catatonia and contemporaneous EEG measurements. Four of these patients showed an improvement in catatonia severity when treated with benzodiazepines, with an average reduction of 6.75 points on the BFCRS. Among patients with generalized periodic discharges, catatonia should be considered, in the appropriate clinical context. Patients with generalized periodic discharges and catatonia may benefit from treatment with empiric trials of benzodiazepines.

Substance specific EEG patterns in mice undergoing slow anesthesia induction

The exact mechanisms and the neural circuits involved in anesthesia induced unconsciousness are still not fully understood. To elucidate them valid animal models are necessary. Since the most commonly used species in neuroscience are mice, we established a murine model for commonly used anesthetics/sedatives and evaluated the epidural electroencephalographic (EEG) patterns during slow anesthesia induction and emergence. Forty-four mice underwent surgery in which we inserted a central venous catheter and implanted nine intracranial electrodes above the prefrontal, motor, sensory, and visual cortex. After at least one week of recovery, mice were anesthetized either by inhalational sevoflurane or intravenous propofol, ketamine, or dexmedetomidine. We evaluated the loss and return of righting reflex (LORR/RORR) and recorded the electrocorticogram. For spectral analysis we focused on the prefrontal and visual cortex. In addition to analyzing the power spectral density at specific time points we evaluated the changes in the spectral power distribution longitudinally. The median time to LORR after start anesthesia ranged from 1080 [1st quartile: 960; 3rd quartile: 1080]s under sevoflurane anesthesia to 1541 [1455; 1890]s with ketamine. Around LORR sevoflurane as well as propofol induced a decrease in the theta/alpha band and an increase in the beta/gamma band. Dexmedetomidine infusion resulted in a shift towards lower frequencies with an increase in the delta range. Ketamine induced stronger activity in the higher frequencies. Our results showed substance-specific changes in EEG patterns during slow anesthesia induction. These patterns were partially identical to previous observations in humans, but also included significant differences, especially in the low frequencies. Our study emphasizes strengths and limitations of murine models in neuroscience and provides an important basis for future studies investigating complex neurophysiological mechanisms.

A study of Electroencephalography Findings and its Prognostic Value in Severe COVID-19 Patients Admitted at Intensive Care Unit

A study of Electroencephalography Findings and its Prognostic Value in Severe COVID-19 Patients Admitted at Intensive Care Unit

Association of Visual-Based Signals with Electroencephalography Patterns in Enhancing the Drowsiness Detection in Drivers with Obstructive Sleep Apnea.

Individuals with obstructive sleep apnea (OSA) face increased accident risks due to excessive daytime sleepiness. PERCLOS, a recognized drowsiness detection method, encounters challenges from image quality, eyewear interference, and lighting variations, impacting its performance, and requiring validation through physiological signals. We propose visual-based scoring using adaptive thresholding for eye aspect ratio with OpenCV for face detection and Dlib for eye detection from video recordings. This technique identified 453 drowsiness (PERCLOS ≥ 0.3 || CLOSDUR ≥ 2 s) and 474 wakefulness episodes (PERCLOS < 0.3 and CLOSDUR < 2 s) among fifty OSA drivers in a 50 min driving simulation while wearing six-channel EEG electrodes. Applying discrete wavelet transform, we derived ten EEG features, correlated them with visual-based episodes using various criteria, and assessed the sensitivity of brain regions and individual EEG channels. Among these features, theta-alpha-ratio exhibited robust mapping (94.7%) with visual-based scoring, followed by delta-alpha-ratio (87.2%) and delta-theta-ratio (86.7%). Frontal area (86.4%) and channel F4 (75.4%) aligned most episodes with theta-alpha-ratio, while frontal, and occipital regions, particularly channels F4 and O2, displayed superior alignment across multiple features. Adding frontal or occipital channels could correlate all episodes with EEG patterns, reducing hardware needs. Our work could potentially enhance real-time drowsiness detection reliability and assess fitness to drive in OSA drivers.