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1.
Am J Hum Genet ; 107(3): 564-574, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32822602

RESUMO

KAT5 encodes an essential lysine acetyltransferase, previously called TIP60, which is involved in regulating gene expression, DNA repair, chromatin remodeling, apoptosis, and cell proliferation; but it remains unclear whether variants in this gene cause a genetic disease. Here, we study three individuals with heterozygous de novo missense variants in KAT5 that affect normally invariant residues, with one at the chromodomain (p.Arg53His) and two at or near the acetyl-CoA binding site (p.Cys369Ser and p.Ser413Ala). All three individuals have cerebral malformations, seizures, global developmental delay or intellectual disability, and severe sleep disturbance. Progressive cerebellar atrophy was also noted. Histone acetylation assays with purified variant KAT5 demonstrated that the variants decrease or abolish the ability of the resulting NuA4/TIP60 multi-subunit complexes to acetylate the histone H4 tail in chromatin. Transcriptomic analysis in affected individual fibroblasts showed deregulation of multiple genes that control development. Moreover, there was also upregulated expression of PER1 (a key gene involved in circadian control) in agreement with sleep anomalies in all of the individuals. In conclusion, dominant missense KAT5 variants cause histone acetylation deficiency with transcriptional dysregulation of multiples genes, thereby leading to a neurodevelopmental syndrome with sleep disturbance, cerebellar atrophy, and facial dysmorphisms, and suggesting a recognizable syndrome.


Assuntos
Atrofia/genética , Doenças Cerebelares/genética , Deficiência Intelectual/genética , Lisina Acetiltransferase 5/genética , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/fisiopatologia , Adolescente , Adulto , Atrofia/diagnóstico por imagem , Atrofia/fisiopatologia , Doenças Cerebelares/diagnóstico por imagem , Doenças Cerebelares/fisiopatologia , Pré-Escolar , Cromatina/genética , Montagem e Desmontagem da Cromatina/genética , Reparo do DNA/genética , Epilepsia/diagnóstico por imagem , Epilepsia/genética , Epilepsia/fisiopatologia , Feminino , Heterozigoto , Histonas/genética , Humanos , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/fisiopatologia , Masculino , Mutação de Sentido Incorreto/genética , Processamento de Proteína Pós-Traducional/genética
2.
Nat Commun ; 11(1): 4014, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782303

RESUMO

Perception reflects not only sensory inputs, but also the endogenous state when these inputs enter the brain. Prior studies show that endogenous neural states influence stimulus processing through non-specific, global mechanisms, such as spontaneous fluctuations of arousal. It is unclear if endogenous activity influences circuit and stimulus-specific processing and behavior as well. Here we use intracranial recordings from 30 pre-surgical epilepsy patients to show that patterns of endogenous activity are related to the strength of trial-by-trial neural tuning in different visual category-selective neural circuits. The same aspects of the endogenous activity that relate to tuning in a particular neural circuit also correlate to behavioral reaction times only for stimuli from the category that circuit is selective for. These results suggest that endogenous activity can modulate neural tuning and influence behavior in a circuit- and stimulus-specific manner, reflecting a potential mechanism by which endogenous neural states facilitate and bias perception.


Assuntos
Rede Nervosa/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Eletrocorticografia , Epilepsia/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia
3.
Nat Commun ; 11(1): 4234, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32843643

RESUMO

Brain-machine interfaces are promising tools to restore lost motor functions and probe brain functional mechanisms. As the number of recording electrodes has been exponentially rising, the signal processing capability of brain-machine interfaces is falling behind. One of the key bottlenecks is that they adopt conventional von Neumann architecture with digital computation that is fundamentally different from the working principle of human brain. In this work, we present a memristor-based neural signal analysis system, where the bio-plausible characteristics of memristors are utilized to analyze signals in the analog domain with high efficiency. As a proof-of-concept demonstration, memristor arrays are used to implement the filtering and identification of epilepsy-related neural signals, achieving a high accuracy of 93.46%. Remarkably, our memristor-based system shows nearly 400× improvements in the power efficiency compared to state-of-the-art complementary metal-oxide-semiconductor systems. This work demonstrates the feasibility of using memristors for high-performance neural signal analysis in next-generation brain-machine interfaces.


Assuntos
Interfaces Cérebro-Computador , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador/instrumentação , Encéfalo/fisiologia , Computadores Analógicos , Sinapses Elétricas/fisiologia , Epilepsia/fisiopatologia , Humanos , Modelos Neurológicos , Transistores Eletrônicos
4.
Neurol Sci ; 41(9): 2345-2351, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32696088

RESUMO

BACKGROUND: During COVID-19 lockdown, non-urgent medical procedures were suspended. Grade of urgency of electroencephalography (EEG) may vary according to the clinical indication, setting, and status of infection of SARS-CoV-2 virus. "Italian Society of Clinical Neurophysiology" (SINC), "Italian League Against Epilepsy" (LICE), and the "Italian Association of Neurophysiology Technologists" (AITN) aimed to provide clinical and technical recommendation for EEG indications and recording standards in this pandemic era. METHODS: Presidents of SINC, LICE, and AITN endorsed three members per each society to formulate recommendations: classification of the degree of urgency of EEG clinical indications, management and behavior of physicians and neurophysiology technologists, hygiene and personal protection standards, and use of technical equipment. RESULTS: Scientific societies endorsed a paper conveying the recommendation for EEG execution in accordance with clinical urgency, setting (inpatients/outpatients), status of SARS-CoV-2 virus infection (positive, negative and uncertain), and phase of governmental restrictions (phase 1 and 2). Briefly, in phase 1, EEG was recommended only for those acute/subacute neurological symptoms where EEG is necessary for diagnosis, prognosis, or therapy. Outpatient examinations should be avoided in phase 1, while they should be recommended in urgent cases in phase 2 when they could prevent an emergency room access. Reduction of staff contacts must be encouraged through rescheduling job shifts. The use of disposable electrodes and dedicated EEG devices for COVID-19-positive patients are recommended. CONCLUSIONS: During the different phases of COVID-19 pandemic, the EEG should be reserved for patients really benefiting from its execution in terms of diagnosis, treatment, prognosis, and avoidance of emergency room access.


Assuntos
Betacoronavirus , Infecções por Coronavirus/fisiopatologia , Eletroencefalografia/normas , Epilepsia/fisiopatologia , Pneumonia Viral/fisiopatologia , Guias de Prática Clínica como Assunto/normas , Sociedades Médicas/normas , Comitês Consultivos/normas , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Surtos de Doenças/prevenção & controle , Epilepsia/diagnóstico , Epilepsia/epidemiologia , Humanos , Itália/epidemiologia , Pessoal de Laboratório Médico/normas , Neurofisiologia/métodos , Neurofisiologia/normas , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia
5.
S Afr Med J ; 110(2): 102-105, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32657678

RESUMO

The compounds present in cannabis have been in use for both recreational and medicinal purposes for many centuries. Changes in the legislation in South Africa have led to an increase in the number of people interested in using these compounds for self-medication. Many of them may approach their general practitioner as the first source of information about possible therapeutic effects. It is important that medical professionals are able to give patients the correct information. Cannabidiol (CBD) is one of the main compounds in cannabis plants, and there is evidence that it can successfully treat certain patients with epilepsy. This review looks at the most recent evidence on the use of CBD in the treatment of epilepsy and explores the mechanisms behind these beneficial effects.


Assuntos
Canabidiol/farmacologia , Cannabis/química , Epilepsia/tratamento farmacológico , Animais , Anticonvulsivantes/isolamento & purificação , Anticonvulsivantes/farmacologia , Canabidiol/isolamento & purificação , Epilepsia/fisiopatologia , Humanos , África do Sul
6.
Epilepsy Behav ; 111: 107262, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32645620

RESUMO

Access to quality healthcare remains a challenge that is complicated by mounting pressures to control costs, and now, as we witness, the unprecedented strain placed on our healthcare delivery systems due to the COVID-19 pandemic. Challenges in healthcare access have driven a need for innovative approaches ensuring connectivity to health providers. Telehealth services and virtual clinics offer accessible disease management pathways for patients living in health resource limited areas or, as in the case of the COVID-19 pandemic, where there may be potential barriers to existing healthcare resources. Those suffering with serious chronic disorders often cannot be seen by a healthcare specialist due to their limited availability, or the lack of a specialist within a reasonable proximity. Epilepsy represents such a disorder where most of the world's population lacks the availability of necessary specialists. Virtual clinics allow for specialist care and an ability to perform necessary ambulatory electroencephalogram (EEG) monitoring by placing the technologies directly in patients' homes or at local clinics near the patients' homes. By moving the diagnostic process out of the hospital or epilepsy center, it becomes possible to overcome growing gaps in neurology services. Virtual clinics have the potential to expand access to high-quality, cost-effective care for the patient. The virtual clinic remotely connects those in need of medical support with specialists anywhere in the world, at any time of the day.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Epilepsia/terapia , Pandemias , Pneumonia Viral , Eletroencefalografia , Epilepsia/epidemiologia , Epilepsia/fisiopatologia , Acesso aos Serviços de Saúde , Humanos , Monitorização Ambulatorial , Telemedicina
7.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 40(7): 972-980, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32701228

RESUMO

OBJECTIVE: To investigate the effects of acid-sensing ion channels (ASICs) on electrophysiological epileptic activities of mouse hippocampal pyramidal neurons in the extracellular acidotic condition. METHODS: We investigated effects of extracellular acidosis on epileptic activities induced by elevated extracellular K + concentration or the application of an antagonist of GABAA receptors in perfusate of mouse hippocampal slices under field potential recordings. We also tested the effects of extracellular acidosis on neuronal excitability under field potential recording and evaluated the changes in epileptic activities of the neurons in response to pharmacological inhibition of ASICs using a specific inhibitor of ASICs. RESULTS: Extracellular acidosis significantly suppressed epileptic activities of the hippocampal neurons by converting ictal-like epileptic activities to non-ictal-like epileptic activities in both high [K +]o and disinhibition models, and also suppressed the intrinsic excitability of the neurons. ASICs inhibitor did not antagonize the inhibitory effect of extracellular acidosis on ictal epileptic activities and intrinsic neuronal excitability, but exacerbated non-ictal epileptic activities of the neurons in extracellular acidotic condition in both high [K+]o and disinhibition models. CONCLUSIONS: ASICs can differentially modulate ictal-like and non-ictallike epileptic activities via its direct actions on excitatory neurons.


Assuntos
Canais Iônicos Sensíveis a Ácido , Acidose , Epilepsia , Células Piramidais , Canais Iônicos Sensíveis a Ácido/metabolismo , Animais , Epilepsia/fisiopatologia , Concentração de Íons de Hidrogênio , Camundongos , Células Piramidais/patologia , Células Piramidais/fisiologia
8.
BMC Neurol ; 20(1): 233, 2020 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-32505173

RESUMO

BACKGROUND: Interictal epileptiform discharges (IEDs) have been proven to impair cognitive function. However, it is not clear whether IEDs disrupt academic performance in children with idiopathic epilepsy, and the contribution of cognitive function deficits to impaired academic performance has not been clarified. This study aimed to examine the cognitive deficits and academic impairment in childhood idiopathic epilepsy with IEDs. METHODS: Ninety-seven childhood idiopathic epilepsy with IEDs, 77 childhood idiopathic epilepsy without IEDs, and 71 healthy controls completed a series of cognitive tests. We analyzed the cognitive performance in several domains including language, mathematics, psychomotor speed, spatial ability, memory, general intelligence, attention and executive functioning. Analysis of variance was conducted to compare the performance on all tests between the three groups. RESULTS: Childhood idiopathic epilepsy with IEDs exhibited not only general cognitive deficits in processing speed, spatial ability, and attention, but also arithmetic impairment. Furthermore, general cognitive deficits could account for the impaired arithmetic performance in childhood idiopathic epilepsy with IEDs. CONCLUSIONS: Our study suggested that IEDs in children with idiopathic epilepsy affected both cognitive function and academic performance, and that the cognitive deficits may be responsible for arithmetic performance impairment.


Assuntos
Desempenho Acadêmico/estatística & dados numéricos , Cognição/fisiologia , Epilepsia/fisiopatologia , Estudos de Casos e Controles , Criança , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Masculino
9.
Nat Commun ; 11(1): 3075, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32555174

RESUMO

The processing steps that lead up to a decision, i.e., the transformation of sensory evidence into motor output, are not fully understood. Here, we combine stereoEEG recordings from the human cortex, with single-lead and time-resolved decoding, using a wide range of temporal frequencies, to characterize decision processing during a rule-switching task. Our data reveal the contribution of rostral inferior parietal lobule (IPL) regions, in particular PFt, and the parietal opercular regions in decision processing and demonstrate that the network representing the decision is common to both task rules. We reconstruct the sequence in which regions engage in decision processing on single trials, thereby providing a detailed picture of the network dynamics involved in decision-making. The reconstructed timeline suggests that the supramarginal gyrus in IPL links decision regions in prefrontal cortex with premotor regions, where the motor plan for the response is elaborated.


Assuntos
Tomada de Decisões , Eletroencefalografia , Lobo Parietal/fisiologia , Adulto , Mapeamento Encefálico , Análise por Conglomerados , Cognição , Análise Discriminante , Eletrodos , Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Rede Nervosa/fisiologia , Processamento de Sinais Assistido por Computador , Análise de Ondaletas , Adulto Jovem
10.
Medicine (Baltimore) ; 99(26): e20823, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590769

RESUMO

Gout is a chronic disease related to uric acid metabolism. It involves crystals of uric acid accumulating in the joints, causing joint pain and releasing cytokines that trigger inflammation. Inflammation is a key component in the pathogenesis of epilepsy. Thus, we conducted a cohort study to investigate if epilepsy is associated with gout and determine the risk of epilepsy in patients with gout.The gout cohort was obtained from the Registry of Catastrophic Illnesses Patient Database (RCIPD). We identified 104,238 patients who were aged 20 years or more and newly diagnosed with gout between 2000 and 2011 and 3 outpatient visits or history of gout-specific hospitalization between 2000 and 2011. Patients without gout were frequency matched with the gout cohort at a 2:1 ratio according to age, sex, comorbidities, and year of gout diagnosis.The gout cohort showed a 1.27-fold higher overall crude hazard ratio (HR) for epilepsy compared with the control cohort. After we adjusted the analyses by age, sex, and comorbidities the gout patients displayed an increased risk of epilepsy compared with the control group (adjusted HR = 1.25, 95% confidence interval = 1.15-1.36).This study revealed a significantly higher risk of epilepsy in patients with gout. It provides further evidence for the debate around the effect of gout on brain health.


Assuntos
Epilepsia/fisiopatologia , Gota/fisiopatologia , Adulto , Idoso , Estudos de Coortes , Correlação de Dados , Epilepsia/epidemiologia , Feminino , Gota/epidemiologia , Humanos , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros/estatística & dados numéricos , Fatores de Risco , Taiwan/epidemiologia
12.
PLoS One ; 15(5): e0230141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413036

RESUMO

Comparative severity assessment of animal models and experimental interventions is of utmost relevance for harm-benefit analysis during ethical evaluation, an animal welfare-based model prioritization as well as the validation of refinement measures. Unfortunately, there is a lack of evidence-based approaches to grade an animal's burden in a sensitive, robust, precise, and objective manner. Particular challenges need to be considered in the context of animal-based neuroscientific research because models of neurological disorders can be characterized by relevant changes in the affective state of an animal. Here, we report about an approach for parameter selection and development of a composite measure scheme designed for precise analysis of the distress of animals in a specific model category. Data sets from the analysis of several behavioral and biochemical parameters in three different epilepsy models were subjected to a principal component analysis to select the most informative parameters. The top-ranking parameters included burrowing, open field locomotion, social interaction, and saccharin preference. These were combined to create a composite measure scheme (CMS). CMS data were subjected to cluster analysis enabling the allocation of severity levels to individual animals. The results provided information for a direct comparison between models indicating a comparable severity of the electrical and chemical post-status epilepticus models, and a lower severity of the kindling model. The new CMS can be directly applied for comparison of other rat models with seizure activity or for assessment of novel refinement approaches in the respective research field. The respective online tool for direct application of the CMS or for creating a new CMS based on other parameters from different models is available at https://github.com/mytalbot/cms. However, the robustness and generalizability needs to be further assessed in future studies. More importantly, our concept of parameter selection can serve as a practice example providing the basis for comparable approaches applicable to the development and validation of CMS for all kinds of disease models or interventions.


Assuntos
Modelos Animais de Doenças , Epilepsia/fisiopatologia , Software , Animais , Variação Biológica da População , Epilepsia/patologia , Feminino , Excitação Neurológica , Locomoção , Ratos , Ratos Sprague-Dawley , Comportamento Social , Comportamento Espacial
13.
Life Sci ; 253: 117692, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32376271

RESUMO

BACKGROUND: Depression is the most significant cause of suicide among neuropsychiatric illnesses. Major depression further affects the quality of life in an individual with epilepsy. The treatment of depression in an epileptic patient could be very challenging because of drug selection or the fact that some antiepileptic drugs are known to cause depression. It has been shown that in addition to the known involvement of the serotonergic pathway in depression, the glutamatergic system is also involved in the evolution of the disease, but this knowledge is limited. This study assessed if induction of epilepsy in rats will cause depressive-like behavior, alters the concentrations of metabotropic receptor 5 (mGluR5), glutamate transport protein (GLAST), glutamate synthase (GS) and brain derived neurotrophic factor (BDNF). MATERIALS AND METHOD: Epilepsy was induced in rats by injecting Pentylenetetrazole at 35 mg/kg every other day. At kindle, rats were subjected to sucrose preference test (SPT) and forced swim test (FST) and decapitated 4 h later. Hippocampal tissue was collected and the BDNF concentration was measured with ELISA; mGluR5 and GS protein expression was measured using western blot while amygdala tissue was used for GLAST expression with flow cytometry. RESULTS: Our results showed that epilepsy leads to depressive-like behavior in rats and alters the glutamatergic system. CONCLUSION: Therefore, we conclude that targeting the glutamate pathway may be a good strategy to alleviate depressive-like behavior associated with epilepsy.


Assuntos
Depressão/fisiopatologia , Epilepsia/fisiopatologia , Ácido Glutâmico/metabolismo , Convulsões Febris/fisiopatologia , Tonsila do Cerebelo/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transportador 1 de Aminoácido Excitatório/metabolismo , Glutamato Sintase/metabolismo , Hipocampo/metabolismo , Masculino , Pentilenotetrazol/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptor de Glutamato Metabotrópico 5/metabolismo
15.
PLoS Biol ; 18(5): e3000685, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32374723

RESUMO

Phase synchronization of neuronal oscillations in specific frequency bands coordinates anatomically distributed neuronal processing and communication. Typically, oscillations and synchronization take place concurrently in many distinct frequencies, which serve separate computational roles in cognitive functions. While within-frequency phase synchronization has been studied extensively, less is known about the mechanisms that govern neuronal processing distributed across frequencies and brain regions. Such integration of processing between frequencies could be achieved via cross-frequency coupling (CFC), either by phase-amplitude coupling (PAC) or by n:m-cross-frequency phase synchrony (CFS). So far, studies have mostly focused on local CFC in individual brain regions, whereas the presence and functional organization of CFC between brain areas have remained largely unknown. We posit that interareal CFC may be essential for large-scale coordination of neuronal activity and investigate here whether genuine CFC networks are present in human resting-state (RS) brain activity. To assess the functional organization of CFC networks, we identified brain-wide CFC networks at mesoscale resolution from stereoelectroencephalography (SEEG) and at macroscale resolution from source-reconstructed magnetoencephalography (MEG) data. We developed a novel, to our knowledge, graph-theoretical method to distinguish genuine CFC from spurious CFC that may arise from nonsinusoidal signals ubiquitous in neuronal activity. We show that genuine interareal CFC is present in human RS activity in both SEEG and MEG data. Both CFS and PAC networks coupled theta and alpha oscillations with higher frequencies in large-scale networks connecting anterior and posterior brain regions. CFS and PAC networks had distinct spectral patterns and opposing distribution of low- and high-frequency network hubs, implying that they constitute distinct CFC mechanisms. The strength of CFS networks was also predictive of cognitive performance in a separate neuropsychological assessment. In conclusion, these results provide evidence for interareal CFS and PAC being 2 distinct mechanisms for coupling oscillations across frequencies in large-scale brain networks.


Assuntos
Encéfalo/fisiologia , Conectoma , Sincronização de Fases em Eletroencefalografia , Encéfalo/diagnóstico por imagem , Epilepsia/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Modelos Neurológicos , Testes Neuropsicológicos
16.
Neurology ; 94(20): e2139-e2147, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32321764

RESUMO

OBJECTIVE: To define and validate criteria for accurate identification of EEG interictal epileptiform discharges (IEDs) using (1) the 6 sensor space criteria proposed by the International Federation of Clinical Neurophysiology (IFCN) and (2) a novel source space method. Criteria yielding high specificity are needed because EEG over-reading is a common cause of epilepsy misdiagnosis. METHODS: Seven raters reviewed EEG sharp transients from 100 patients with and without epilepsy (diagnosed definitively by video-EEG recording of habitual events). Raters reviewed the transients, randomized, and classified them as epileptiform or nonepileptiform in 3 separate rounds: in 2, EEG was reviewed in sensor space (scoring the presence/absence of each IFCN criterion for each transient or classifying unrestricted by criteria [expert scoring]); in the other, review and classification were performed in source space. RESULTS: Cutoff values of 4 and 5 criteria in sensor space and analysis in source space provided high accuracy (91%, 88%, and 90%, respectively), similar to expert scoring (92%). Two methods had specificity exceeding the desired threshold of 95%: using 5 IFCN criteria as cutoff and analysis in source space (both 95.65%); the sensitivity of these methods was 81.48% and 85.19%, respectively. CONCLUSIONS: The presence of 5 IFCN criteria in sensor space and analysis in source space are optimal for clinical implementation. By extracting these objective features, diagnostic accuracy similar to expert scorings is achieved. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that IFCN criteria in sensor space and analysis in source space have high specificity (>95%) and sensitivity (81%-85%) for identification of IEDs.


Assuntos
Encéfalo/fisiopatologia , Eletroencefalografia , Epilepsia/fisiopatologia , Magnetoencefalografia , Adolescente , Adulto , Criança , Pré-Escolar , Eletroencefalografia/métodos , Epilepsias Parciais/fisiopatologia , Epilepsia/diagnóstico , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino , Sensibilidade e Especificidade , Gravação em Vídeo/métodos , Adulto Jovem
17.
J Integr Neurosci ; 19(1): 1-9, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32259881

RESUMO

Electroencephalography is the recording of brain electrical activities that can be used to diagnose brain seizure disorders. By identifying brain activity patterns and their correspondence between symptoms and diseases, it is possible to give an accurate diagnosis and appropriate drug therapy to patients. This work aims to categorize electroencephalography signals on different channels' recordings for classifying and predicting epileptic seizures. The collection of the electroencephalography recordings contained in the dataset attributes 179 information and 11,500 instances. Instances are of five categories, where one is the symptoms of epilepsy seizure. We have used traditional, ensemble methods and deep machine learning techniques highlighting their performance for the epilepsy seizure detection task. One dimensional convolutional neural network, ensemble machine learning techniques like bagging, boosting (AdaBoost, gradient boosting, and XG boosting), and stacking is implemented. Traditional machine learning techniques such as decision tree, random forest, extra tree, ridge classifier, logistic regression, K-Nearest Neighbor, Naive Bayes (gaussian), and Kernel Support Vector Machine (polynomial, gaussian) are used for classifying and predicting epilepsy seizure. Before using ensemble and traditional techniques, we have preprocessed the data set using the Karl Pearson coefficient of correlation to eliminate irrelevant attributes. Further accuracy of classification and prediction of the classifiers are manipulated using k-fold cross-validation methods and represent the Receiver Operating Characteristic Area Under the Curve for each classifier. After sorting and comparing algorithms, we have found the convolutional neural network and extra tree bagging classifiers to have better performance than all other ensemble and traditional classifiers.


Assuntos
Encéfalo/fisiopatologia , Eletroencefalografia , Epilepsia/diagnóstico , Aprendizado de Máquina , Convulsões/diagnóstico , Epilepsia/fisiopatologia , Humanos , Curva ROC , Convulsões/fisiopatologia , Processamento de Sinais Assistido por Computador
18.
PLoS Biol ; 18(4): e3000659, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32243450

RESUMO

Putting a name to a face is a highly common activity in our daily life that greatly enriches social interactions. Although this specific person-identity association becomes automatic with learning, it remains difficult and can easily be disrupted in normal circumstances or neurological conditions. To shed light on the neural basis of this important and yet poorly understood association between different input modalities in the human brain, we designed a crossmodal frequency-tagging paradigm coupled to brain activity recording via scalp and intracerebral electroencephalography. In Experiment 1, 12 participants were presented with variable pictures of faces and written names of a single famous identity at a 4-Hz frequency rate while performing an orthogonal task. Every 7 items, another famous identity appeared, either as a face or a name. Robust electrophysiological responses were found exactly at the frequency of identity change (i.e., 4 Hz / 7 = 0.571 Hz), suggesting a crossmodal neural response to person identity. In Experiment 2 with twenty participants, two control conditions with periodic changes of identity for faces or names only were added to estimate the contribution of unimodal neural activity to the putative crossmodal face-name responses. About 30% of the response occurring at the frequency of crossmodal identity change over the left occipito-temporal cortex could not be accounted for by the linear sum of unimodal responses. Finally, intracerebral recordings in the left ventral anterior temporal lobe (ATL) in 7 epileptic patients tested with this paradigm revealed a small number of "pure" crossmodal responses, i.e., with no response to changes of identity for faces or names only. Altogether, these observations provide evidence for integration of verbal and nonverbal person identity-specific information in the human brain, highlighting the contribution of the left ventral ATL in the automatic retrieval of face-name identity associations.


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Lobo Temporal/fisiologia , Eletroencefalografia , Epilepsia/fisiopatologia , Epilepsia/psicologia , Face , Feminino , Humanos , Masculino , Nomes , Testes Neuropsicológicos , Experimentação Humana não Terapêutica , Adulto Jovem
19.
PLoS Comput Biol ; 16(4): e1007661, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32348299

RESUMO

In most neuronal models, ion concentrations are assumed to be constant, and effects of concentration variations on ionic reversal potentials, or of ionic diffusion on electrical potentials are not accounted for. Here, we present the electrodiffusive Pinsky-Rinzel (edPR) model, which we believe is the first multicompartmental neuron model that accounts for electrodiffusive ion concentration dynamics in a way that ensures a biophysically consistent relationship between ion concentrations, electrical charge, and electrical potentials in both the intra- and extracellular space. The edPR model is an expanded version of the two-compartment Pinsky-Rinzel (PR) model of a hippocampal CA3 neuron. Unlike the PR model, the edPR model includes homeostatic mechanisms and ion-specific leakage currents, and keeps track of all ion concentrations (Na+, K+, Ca2+, and Cl-), electrical potentials, and electrical conductivities in the intra- and extracellular space. The edPR model reproduces the membrane potential dynamics of the PR model for moderate firing activity. For higher activity levels, or when homeostatic mechanisms are impaired, the homeostatic mechanisms fail in maintaining ion concentrations close to baseline, and the edPR model diverges from the PR model as it accounts for effects of concentration changes on neuronal firing. We envision that the edPR model will be useful for the field in three main ways. Firstly, as it relaxes commonly made modeling assumptions, the edPR model can be used to test the validity of these assumptions under various firing conditions, as we show here for a few selected cases. Secondly, the edPR model should supplement the PR model when simulating scenarios where ion concentrations are expected to vary over time. Thirdly, being applicable to conditions with failed homeostasis, the edPR model opens up for simulating a range of pathological conditions, such as spreading depression or epilepsy.


Assuntos
Potenciais de Ação , Eletrofisiologia/métodos , Modelos Neurológicos , Neurônios/fisiologia , Animais , Cálcio/metabolismo , Calibragem , Simulação por Computador , Dendritos/fisiologia , Difusão , Epilepsia/fisiopatologia , Hipocampo/fisiopatologia , Homeostase , Humanos , Canais Iônicos/metabolismo , Íons , Potenciais da Membrana , Ratos
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