Electroencephalographic Examination Research Articles

Use of sedation-awakening electroencephalography in dogs with epilepsy.

Electroencephalography (EEG) recording protocols have been standardized for humans. Although the utilization of techniques in veterinary medicine is increasing, a standard protocol has not yet been established. Assessment of a sedation-awakening EEG protocol in dogs. Electroencephalography examination was performed in a research colony of 6 nonepileptic dogs (control [C]) and 12 dogs with epilepsy admitted to the clinic because of the epileptic seizures. It was a prospective study with retrospective control. Dogs with epilepsy were divided into 2 equal groups, wherein EEG acquisition was performed using a "sedation" protocol (IE-S, n = 6) and a "sedation-awakening" protocol (IE-SA, n = 6). All animals were sedated using medetomidine. In IE-SA group, sedation was reversed 5 minutes after commencing the EEG recording by injecting atipamezole IM. Type of background activity (BGA) and presence of EEG-defined epileptiform discharges (EDs) were evaluated blindly. Statistical significance was set at P > 0.05. Epileptiform discharges were found in 1 of 6 of the dogs in group C, 4 of 6 of the dogs in IE-S group, and 5 of 6 of the dogs in IE-SA group. A significantly greater number of EDs (spikes, P = .0109; polyspikes, P = .0109; sharp waves, P = .01) were detected in Phase 2 in animals subjected to the "sedation-awakening" protocol, whereas there was no statistically significant greater number of discharges in sedated animals. A "sedation-awakening" EEG protocol could be of value for ambulatory use if repeated EEG recordings and monitoring of epilepsy in dogs is needed.

Development of spontaneous recurrent seizures accompanied with increased rates of interictal spikes and decreased hippocampal delta and theta activities following extended kindling in mice

Interictal epileptiform discharges refer to aberrant brain electrographic signals between seizures and feature intermittent interictal spikes (ISs), sharp waves, and/or abnormal rhythms. Recognition of these epileptiform activities by electroencephalographic (EEG) examinations greatly aids epilepsy diagnosis and localization of the seizure onset zone. ISs are a major form of interictal epileptiform discharges recognized in animal models of epilepsy. Progressive changes in IS waveforms, IS rates, and/or associated fast ripple oscillations have been shown to precede the development of spontaneous recurrent seizures (SRS) in various animal models. IS expressions in the kindling model of epilepsy have been demonstrated but IS changes during the course of SRS development in extended kindled animals remain to be detailed. We hence addressed this issue using a mouse model of kindling-induced SRS. Adult C57 black mice received twice daily hippocampal stimulations until SRS occurrence, with 24-h EEG monitoring performed following 50, 80, and ≥ 100 stimulations and after observation of SRS. In the stimulated hippocampus, increases in spontaneous ISs rates, but not in IS waveforms nor IS-associated fast ripples, along with decreased frequencies of hippocampal delta and theta rhythms, were observed before SRS onset. Comparable increases in IS rates were further observed in the unstimulated hippocampus, piriform cortex, and entorhinal cortex, but not in the unstimulated parietal cortex and dorsomedial thalamus. These data provide original evidence suggesting that increases in hippocampal IS rates, together with reductions in hippocampal delta and theta rhythms are closely associated with development of SRS in a rodent kindling model.

Combination of stem cell and repetitive transcranial magnetic stimulation in acute ischaemic stroke as a promising treatment: A case report

Stroke is a major contributor to long-term disability and its incidence continues to rise annually. This case report aimed to explore the promising benefits of combining stem cell therapy with repetitive transcranial magnetic stimulation (rTMS) in managing acute ischaemic stroke patients. A 62-year-old male presented with left-sided hemiparesis and hemineglect, as well as a cognitive disturbance in the attention domain. His medical history included uncontrolled hypertension over decades and diabetes mellitus for five years. A non-contrast head computed tomography (CT) scan revealed infarction in the right middle cerebral artery (MCA), with an initial National Institutes of Health Stroke Scale (NIHSS) of 13 upon admission to the Emergency Room. The infection and tumour markers were conducted to confirm no contraindication in this patient receiving stem cell therapy. Following the acute phase, the patient underwent a comprehensive treatment regimen involving both stem cell therapy and serial rTMS. Clinical assessments included NIHSS, Barthel Index, and Fugl-Meyer Assesement to evaluate neurological deficits. Additionally, the Montreal Cognitive Assessment-Indonesian version (MoCA-INA) assessment, electroencephalography examination and motor threshold were conducted. The results of this case report revealed noteworthy improvements in NIHSS, motoric strength, and cognitive function post-treatment. In this case report, improvement in clinical outcomes was obtained in the form of motor strength and higher cortical function. Stem cell therapy combined with rTMS has good potential in treating various neuroregenerative and rehabilitative aspects in ischaemic stroke patients.

Study of EEG sensitivity and specificity in loss of conciousness in adolescents

IntroductionAlthough the etiological diagnosis of loss of consciousness is essentially based on a careful history and clinical examination, electroencephalography (EEG) remains an important investigative tool.Objectives The aim of this study was to identify the value of EEG in the management of adolescents with recurrent bouts of faintingMethodsThis was a retrospective descriptive study conducted from January 2019 to May 2022. We included all adolescents referred to the functional explorations department at Habib Bourguiba hospital, Tunisia for Electroencephalogram (EEG) as part of a workup to explore recurrent episodes of loss of consciousness.ResultsA total of 55 adolescents were included in this study, with a mean age of 15.4±2.3 and a 72.4% female proportion.The delay between the EEG and the onset of the seizure was greater than one week.67.3% of patients were referred by the child psychiatry department.29.1% of the 55 EEG reports were pathological. Epileptiform discharges were noted in 56.3% of adolescents. Slow waves were found in 43.7% of cases. The location of the abnormalities was predominantly frontal. Patients with temporal EEG anomalies had a notion of ascending epigastric pain preceding loss of consciousness in 90% of cases. Adolescents with EEGs containing epileptiform abnormalities had a history of paroxysmal movements in 30% of cases. The sensitivity of the EEG was estimated to be around 25%, and the specificity around 79%.ConclusionsAlthough the clinical examination is of great importance in the etiological diagnosis of loss of consciousness, the EEG remains a complementary examination of non-negligible interest in the etiological investigation.Disclosure of InterestNone Declared

Speech disorders in genetically determined forms of epilepsy in children. Clinical observations

BACKGROUND: Speech disorders in children are one of the pressing problems of child neurology. In recent years, much attention has been paid to studying the genetic aspects of the development of speech disorders in children with epilepsy. Speech function in childhood is vulnerable, and its violation has a number of significant consequences. Specialists from different disciplines focus on specific aspects of speech disorders. Speech therapists consider speech disorders based on linguistic criteria, psychologists evaluate the psychological characteristics of children with speech disorders. The rapid development of genetic research, the availability of many molecular genetic tests, especially such a method as next generation sequencing, allowed us to pay more attention to the study of genetic aspects of the development of speech disorders in children with epilepsy.
 AIM: to present options for speech disorders in genetically determined forms of epilepsy in children based on clinical examples.
 RESULTS: The article analyzes 3 clinical cases of epilepsy in children, combined with speech pathology (2 boys and 1 girl aged 2 to 5 years). The data of anamnesis of life and disease, neurological examination with assessment of speech function, results of genetic research, electroencephalographic examination and magnetic resonance imaging are presented.
 CONCLUSION: All patients are united by a combination of speech disorders, epileptic seizures, and the presence of genetic pathologies that are responsible for speech function. These clinical observations demonstrate the need for a comprehensive, multidisciplinary approach both at the stage of early diagnosis of speech impairment in children with epileptic seizures and at the stage of further treatment of such patients.

Characteristics of Autism Spectrum Disorder among a Sample of Egyptian Children

Background Autism spectrum disorder (ASD) is a biologically based neurodevelopmental disorder characterized by impairments in two major domains; deficits in social communication and social interaction and restricted repetitive patterns of behavior, interests and activities. Aim of the Work Understanding and correlating the socioeconomic status (SES), clinical characteristics and the severity of ASD. Patients and Methods 100 autistic patients were assessed using DSM-V criteria, intelligence quotient (IQ) assessment using Stanford Binnet intelligence scale, assessment of severity of autistic symptoms using childhood autism rating scale (CARS), and psychometric evaluation for comorbid psychiatric conditions by using Pediatric Symptoms Checklist (PSCL), Full clinical examination, neurological examination, Electroencephalography (EEG) for some patient & socioeconomic status (SES) assessment were also done. Results Severity of ASD was correlated with each of motor & social delay (p = 0.007) (p = 0.000) respectively, impairment in Sphincter control (p = 0.012), imitation impairment (p = 0.010) and stereotypic behavior (p = 0.015. Our patients had comorbidities in the form of; gastrointestinal tract (GIT) symptoms, eating disorders and EEG findings (p = 0.004) (p = 0.005) (p = 0.038) respectively. Our patients mainly belonged to middle SES (57%) and severity of ASD was correlated with family possessions domain of SES (p = 0.001). Children who belonged to high SES were more likely to be diagnosed earlier (p = 0.016) with better IQ (p = 0.003) than those from lower SES. Conclusion It is important for developing countries to have their own research and to increase public awareness in all socioeconomic strata and establish integrated services for autism.

Algorithms of diagnosis and therapy of a primary depressive episode

Depressive disorders are among the most widespread forms of mental pathology with significant medical and social consequences and require adequate and timely medical assistance. It is known that algorithms are effective methods of optimizing the provision of psychiatric care in order to prevent the development of therapy-resistant forms of mental pathology and reduce their treatment costs, which is particularly relevant in the case of a primary depressive episode (PDE). The aim of the work is to develop algorithms for rapid diagnosis and therapy of the PDE. Materials and methods. During 2018–2021, 131 patients (49 men and 82 women) with the PDE who sought outpatient psychiatric help were clinically examined. All subjects were tested to determine the level of depressive disorder, according to the unified clinical protocol of highly specialized medical care, according to the Hamilton Rating Scale for Depression, Hamilton Anxiety Rating Scale, and the Clinical Global Impressions Scale. The clinical-ethological description consisted of three stages: at the first stage, at a patients’ first visit, a general description within the framework of a clinical and psychopathological examinations; at the second stage, the clinical-ethological characteristics of non-verbal behavior were studied; at the last, third stage, non-verbal behavior was recoded into ethological elements according to A. A. Korobov’s glossary (1991). Statistical analysis was performed using the Statistica 10 license package of application programs. Results. An algorithm for the PDE diagnosis has been developed based upon four stages: the first one – the symptomatic state diagnosis; the second – clinical-ethological analysis of depressive phenomenon signs and a neurophysiological electroencephalographic (EEG) examination; the third – psycho-experimental examinations using appropriate tools; the fourth – structuring of the obtained diagnostic data, diagnosis verification and development of therapeutic intervention tactics. A therapeutic algorithm for the PDE treatment was also developed and proposed: at the first stage – use of existing antidepressants with proven clinical effectiveness; at the second – switching from a drug in case of its ineffectiveness within 3–4 weeks to another drug with a different mechanism of action; at the third – in case of the previous stage ineffectiveness, using a combination antidepressant therapy (combining drugs of different groups); at the fourth – application of therapeutic schemes using diuretics, pathogenetic psychotherapy and electroconvulsive therapy. Conclusions. The proposed diagnostic and treatment algorithms are reliable enough to detect and treat such a category as the primary depressive episode. The effectiveness of personalized comprehensive diagnostic and treatment methods for these conditions should be based on the principles of phasing, comprehensiveness, using integrated approaches, combining therapies aimed at developing an adequate attitude to a disease state, mitigating the intensity of negative emotions, restoring internal and external resources of patients.

Overview of current software capabilities for EEG recording and analyzing

This article is aimed at familiarizing medical specialists involved in the registration and analysis of electroencephalographic (EEG) examinations with the basic principles of work and the capabilities of current computer software for EEG recording and analyzing. Understanding the basics of how the software works should help medical staff use all its functionality correctly and ultimately improve the quality of medical care. The basic and innovative capabilities of computer software in the field of mathematical processing and analysis of EEG signals are discussed, the limitations of using mathematical processing methods are described.

Disturbance of functional brain networks and cognitive decline in Parkinson's disease: Severe cerebral small vessel disease aggravates this relationship

IntroductionSeveral studies have identified a relationship between functional brain network disturbance and cognitive decline in people with Parkinson's disease (PwP); however, few studies have explored whether cerebral small vessel disease (CSVD) burden modifies this relationship. This study aimed to investigate the potential moderating effect of CSVD on the relationship between functional brain network disturbance and cognitive decline in PwP. MethodsWe prospectively recruited 61 PwP from Beijing Tiantan Hospital between October 2021 to September 2022. The Montreal Cognitive Assessment (MoCA) score was used to assess cognition. CSVD imaging markers were evaluated following the STandards for ReportIng Vascular changes on nEuroimaging instructions, and the CSVD burden score was calculated. The functional connectivity indicator was obtained and calculated using quantitative electroencephalography examination. The moderating effect of CSVD burden on the relationship between functional brain network disturbance and cognitive decline was examined using hierarchical linear regression. ResultsForty-six of 61 (75.4%) PwP had cognitive impairment. Higher global weighted phase lag index (wPLI) values in beta1 bands were significantly associated with lower adjusted MoCA scores. CSVD burden aggravated the effect of the global wPLI in beta1 bands on adjusted MoCA scores. This effect was reinforced by the high level of CSVD burden. ConclusionsHigher wPLI indicates a possible pathological activation of functional brain networks that are associated with cognitive decline in PwP, and the high level of CSVD burden aggravates this relationship.

The structure of modern EEG recorder

The article is aimed at familiarizing medical specialists involved in registration and analysis of electroencephalographic (EEG) examinations with the basic principles of operation and the design of a modern EEG recorder. Understanding the technical fundamentals behind operation of EEG equipment should help medical personnel to correctly use all its capabilities and ultimately improve quality of medical care. The basic diagram of the electroencephalograph operation, the types and features of EEG electrodes, the opportunities and limitations of digitally processed bioelectric signals are discussed. A review on the main technical characteristics of EEG equipment and their influence on the quality of the recorded signal is presented.

A practical value of systematic reviews and meta-analyses on prevalence of EEG abnormalities in COVID-19

During the COVID-19 pandemics, the amount and volume of electroencephalographic (EEG) examinations have been limited for safety reasons. This has complicated not only an identification of specific EEG correlates of the disease but also an assessment of non-specific EEG changes in pa- tients with COVID-19, raising the question of detection of factors and the degree of their impact on prevalence of EEG abnormalities in COVID-19. In the PubMed database, three meta-analyses and three systematic reviews were selected on keywords “COVID-19”, “EEG”, “systematic review”, and “meta-analysis” in order to compare values of the prevalence of EEG abnormalities in patients with COVID-19. The systematic reviews and meta-analyses, which had been performed since 2020 and assessed the prevalence of EEG abnormalities in patients with COVID-19, had differences in their final results despite of an application of the same mathematical methods, criteria for classification of phenomena, usage of one limited base of sources with EEG results (the percentage of overlapped outcome data in the selected reviews and meta-analyses ranged from 22 % to 100 %). Differences between works, which were included in this article, on qualitative and quantitative values of degree of brain functional activity changes in a part of patients with COVID-19 have a sufficiently random nature due to not only volumes of the samples, but also a number of other subjective and objec- tive factors. The results of the presented systematic reviews and meta-analyses suggest, that not all of the obtained EEG data might be extrapolated on a cohort of patients with COVID-19, as the vast majority of patients with COVID (from 85 % to 100 %) examined with EEG had non-specific EEG-changes of a various genesis. A detection of the prevalence of non-specific EEG abnormalities in COVID-19 could have practical implication, particularly for prognosis of outcomes, only on condition of EEG analysis in samples of patients united by a certain common criterion, such as age, presence of certain neurological symptom/syndrome, specific neurological pathology in their anamnesis, etc.

MODULAÇÃO DE ONDAS CEREBRAIS EM PACIENTES COM LESÃO MEDULAR E DOR: UMA ANÁLISE TRANSVERSAL

ABSTRACT Objective: This study aimed to describe the encephalographic electrical rhythm pattern of the Alpha wave in patients with traumatic spinal cord injury in the thoracic spine. Methodology: This is a cross-sectional observational study conducted from January to March 2022. A total of 20 patients with traumatic spinal cord injury were included in the study and divided into two groups, with pain symptoms and without pain symptoms. Both groups were submitted for evaluation for population characterization, identification of the presence of pain and the possible presence of signs and symptoms of central sensitization and quantitative electroencephalographic examination. Results: Comparing them, it was possible to observe a reduction of 38.7% (2.69µV; 95%CI 1.28 to 4.09) in the Alpha 2 wave (10-12 Hz) in the group with pain symptoms. This alteration was identified in the parietal lobe, mainly in PZ. Conclusion: We observed a selective reduction of Alpha 2 waves, mainly in the parietal region (PZ), in spinal cord injury patients with pain compared to spinal cord injury patients without pain. Level of Evidence III; Diagnostic Studies.

Evaluation of pre- and post-transplant electroencephalographic examination in hematopoietic stem cell transplant patients

<p>Haemato&shy;poietic stem cell transplantation (HSCT) is one of the most effective treatment methods for many malignant and non-malignant diseases. In this study, we aimed to detect electroencephalographic (EEG) anomalies at an early stage in patients who underwent allogeneic and autologous HSCT and required the management of potentially life-threatening non-convulsive seizures.</p>. <p>The study was conducted with 53 patients. The age, gender, HSCT type (allogeneic or autologous), and treatment regimens applied before and after HSCT were recorded. All patients underwent EEG monitoring twice, once on the first day of hospitalization and again one week after conditioning regimens began and HSCT was performed.</p>. <p>When the pre-transplant EEG findings were examined, 34 (64.2%) patients had normal EEGs and 19 (35.8%) had abnormal EEGs. After transplantation, 27 (50.9%) had normal EEG findings, 16 (30.2%) had a basic activity disorder, 6 (11.3%) had a focal anomaly, and 4 (7.5%) had a ge&shy;ne&shy;ra&shy;lised anomaly. In the allogeneic group, the anomaly rate in post-transplant EEGs was significantly higher than that in the auto&shy;lo&shy;gous group (p&lt;0.05).</p>. <p>It is important to consider the likelihood of epileptic seizures in the clinical follow-up of HSCT patients. EEG monitoring is crucial for the early diagnosis and treat&shy;ment of such non-convulsive clinical ma&shy;ni&shy;festations.&nbsp;</p>.

Phase Lag Analysis Scalp Electroencephalography May Predict Seizure Frequencies in Patients with Childhood Epilepsy with Centrotemporal Spikes.

Childhood epilepsy with centrotemporal spikes (CECTS) is the most common epilepsy syndrome in school-aged children. However, predictors for seizure frequency are yet to be clarified using the phase lag index (PLI) analyses. We investigated PLI of scalp electroencephalography data at onset to identify potential predictive markers for seizure times. We compared the PLIs of 13 patients with CECTS and 13 age- and sex-matched healthy controls. For the PLI analysis, we used resting-state electroencephalography data (excluding paroxysmal discharges), and analyzed the mean PLIs among all electrodes and between interest electrodes (C3, C4, P3, P4, T3, and T4) and other electrodes. Furthermore, we compared PLIs between CECTS and control data and analyzed the associations between PLIs and total seizure times in CECTS patients. No differences were detected in clinical profiles or visual electroencephalography examinations between patients with CECTS and control participants. In patients with CECTS, the mean PLIs among all electrodes and toward interest electrodes were higher at the theta and alpha bands and lower at the delta and gamma bands than those in control participants. Additionally, the mean PLIs toward interest electrodes in the beta frequency band were negatively associated with seizure times (P = 0.02). The resting-state delta, theta, alpha, and gamma band PLIs might reflect an aberrant brain network in patients with CECTS. The resting-state PLI among the selected electrodes of interest in the beta frequency band may be a predictive marker of seizure times in patients with CECTS.

Warm ears, a red flag for sleepiness?

Core body and skin temperatures are intimately linked to sleep and alertness. The distal-to-proximal skin temperature gradient has been described as a good physiological predictor for sleep onset. Increased ear skin temperature is often caused by increased blood flow reflected in redness, which is commonly noticed in people who are sleepy, especially anecdotally in children. Nonetheless, no prior study investigated the possible relation between sleepiness and ear skin temperature as a separate measurement. We assessed the relation between ear skin temperature and sleepiness in patients undergoing regular electroencephalographic examinations, because of suspicion of epilepsy, both without and after sleep deprivation. Subjective sleepiness was measured using the Stanford Sleepiness Scale, and objective sleepiness by determining sleep onset with electroencephalography. Distal, proximal and ear skin temperature were measured repeatedly using wireless measurement devices (iButtons). Forty-four adult patients were included. Ear skin temperature correlates weakly with distal skin temperature (r= 0.174, p< 0.001) and distal-to-proximal gradient (r= 0.160, p< 0.001), but not with proximal skin temperature (r= -0.001, p= 0.975). Ear skin temperature increased significantly in a subgroup of 13 patients, between 5 and 1 min before sleep onset (p= 0.002; η2 = 0.059), even though this increase was also associated with supine posture. iButtons is a valid method to measure ear skin temperature, which appears to function partly like a distal and partly like a proximal skin temperature measurement. Change in ear skin temperature is associated with sleep onset and supine posture.

Multimodal neuroimaging verification of ganglioglioma associated with neuronal heterotopy in an adult patient without epileps

Gangliogliomas are known to be rare and mainly slow-growing benign primary central nervous system tumors, most frequently occurring in children and young adults. They are the most common epilepsy-associated tumors, which frequent location is the temporal lobe. Surgery often seems to be the best approach in controlling seizures in such patients. This paper deals with a rare case of ganglioglioma in a young adult patient with a temporal lobe tumor associated with neuronal heterotopy of white matter, but without epilepsy. Long-term dynamic observation including in-depth clinical, electroencephalographic, radiologic, and postsurgical histologic examination confirmed the documented neoplastic process without any manifestation of seizures over ten years. Surgical intervention was based on the results of a multimodal radiological examination, which demonstrated the presence of neoplasm in the structure of the pathological substrate of unclear etiology.

Close patient observation and electroencephalography play an important role in the diagnosis of rare diseases. Presentation of a case of Creutzfeldt-Jakob disease

Creutzfeldt–Jakob disease is a rare, progressive spongiform encephalopathy caused by infectious proteins called prions. It is characterised by rapidly progressive dementia accompanied by cerebellar, visual, extrapyramidal, and pyramidal symptoms, as well as myoclonus and mutism in later stage of the disease. The most common type is sporadic Creutzfeldt– Jakob disease, accounting for 85% of all cases. Treatment of the disease is symptomatic. An important role in making the diagnosis is attributed to the observation of the patient and electroencephalography, showing characteristic cyclical discharges. We present the case of a patient whose first symptoms were psychiatric in nature, and who was diagnosed with Creutzfeldt–Jakob disease based on careful observation, presence of myoclonus, and repeated electroencephalography examinations in which typical 1–2 seconds of sharp and slow wave discharges appeared. By presenting this case of severe progressive encephalopathy, we would like to highlight the fact that even in the age of modern diagnostic methods, electroencephalography, which has been in use for many years, may be crucial in the diagnostic process. We would also like to point out that the initial symptoms of Creutzfeldt–Jakob disease may suggest a psychiatric disorder.

The neural basis of authenticity recognition in laughter and crying

Deciding whether others’ emotions are genuine is essential for successful communication and social relationships. While previous fMRI studies suggested that differentiation between authentic and acted emotional expressions involves higher-order brain areas, the time course of authenticity discrimination is still unknown. To address this gap, we tested the impact of authenticity discrimination on event-related potentials (ERPs) related to emotion, motivational salience, and higher-order cognitive processing (N100, P200 and late positive complex, the LPC), using vocalised non-verbal expressions of sadness (crying) and happiness (laughter) in a 32-participant, within-subject study. Using a repeated measures 2-factor (authenticity, emotion) ANOVA, we show that N100’s amplitude was larger in response to authentic than acted vocalisations, particularly in cries, while P200’s was larger in response to acted vocalisations, particularly in laughs. We suggest these results point to two different mechanisms: (1) a larger N100 in response to authentic vocalisations is consistent with its link to emotional content and arousal (putatively larger amplitude for genuine emotional expressions); (2) a larger P200 in response to acted ones is in line with evidence relating it to motivational salience (putatively larger for ambiguous emotional expressions). Complementarily, a significant main effect of emotion was found on P200 and LPC amplitudes, in that the two were larger for laughs than cries, regardless of authenticity. Overall, we provide the first electroencephalographic examination of authenticity discrimination and propose that authenticity processing of others’ vocalisations is initiated early, along that of their emotional content or category, attesting for its evolutionary relevance for trust and bond formation.

Impact of forest fire smoke on the state of the central nervous system of rats

Introduction. The adverse negative effect of forest fire smoke on human health represents a unique interdisciplinary challenge to the scientific community. The influence of forest fire smoke on locomotor activity, cognitive indices, and brain bioelectrical activity parameters in exposed rats is presented. Materials and methods. Experimental studies were carried out on outbred white male rats. The animals of the experimental group were exposed to smoke inhalation forest fire for one day. Immediately after the end of the exposure, the animals were examined, including testing in an open field and Morris water maze, as well as an electroencephalographic examination. Results. At twenty-four-hour exposure to wildfire smoke in the model, conditions showed increasing motor and research activity of male rats against the backdrop of growing anxiety. Disorders of indicators of spatial memory and navigation learning were not revealed. On the encephalogram of the exposed animals, in comparison with the control group, the δ-rhythm range predominated, more pronounced in the leads of the right hemisphere. A decrease in the power spectrum and the average amplitude β1-rhythm, as well as a tendency to decrease the average amplitude of θ-rhythm, were revealed. The indices of the primary EEG rhythms did not have statistically significant differences when compared with the control group. Conclusion. The results showed that forest fire smoke leads to changes in the bioelectric activity of brain structures and dysregulation of individual behaviour in animals, all of which may indicate the formation of increased levels of stressing beyond physiological adaptation.

A Primer on Hyperdimensional Computing for iEEG Seizure Detection.

A central challenge in today's care of epilepsy patients is that the disease dynamics are severely under-sampled in the currently typical setting with appointment-based clinical and electroencephalographic examinations. Implantable devices to monitor electrical brain signals and to detect epileptic seizures may significantly improve this situation and may inform personalized treatment on an unprecedented scale. These implantable devices should be optimized for energy efficiency and compact design. Energy efficiency will ease their maintenance by reducing the time of recharging, or by increasing the lifetime of their batteries. Biological nervous systems use an extremely small amount of energy for information processing. In recent years, a number of methods, often collectively referred to as brain-inspired computing, have also been developed to improve computation in non-biological hardware. Here, we give an overview of one of these methods, which has in particular been inspired by the very size of brains' circuits and termed hyperdimensional computing. Using a tutorial style, we set out to explain the key concepts of hyperdimensional computing including very high-dimensional binary vectors, the operations used to combine and manipulate these vectors, and the crucial characteristics of the mathematical space they inhabit. We then demonstrate step-by-step how hyperdimensional computing can be used to detect epileptic seizures from intracranial electroencephalogram (EEG) recordings with high energy efficiency, high specificity, and high sensitivity. We conclude by describing potential future clinical applications of hyperdimensional computing for the analysis of EEG and non-EEG digital biomarkers.