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1.
Artigo em Inglês | MEDLINE | ID: mdl-32730915

RESUMO

In December 2019, the first case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) infection was reported. In only few weeks it has caused a global pandemic, with mortality reaching 3.4%, mostly due to a severe pneumonia. However, the impact of SARS-CoV-2 virus on the central nervous system (CNS) and mental health outcomes remains unclear. Previous studies have demonstrated the presence of other types of coronaviruses in the brain, especially in the brainstem. There is evidence that the novel coronavirus can penetrate CNS through the olfactory or circulatory route as well as it can have an indirect impact on the brain by causing cytokine storm. There are also first reports of neurological signs in patients infected by the SARS-Cov-2. They show that COVID-19 patients have neurologic manifestations like acute cerebrovascular disease, conscious disturbance, taste and olfactory disturbances. In addition, there are studies showing that certain psychopathological symptoms might appear in infected patients, including those related to mood and psychotic disorders as well as post-traumatic stress disorder. Accumulating evidence also indicates that the pandemic might have a great impact on mental health from the global perspective, with medical workers being particularly vulnerable. In this article, we provide a review of studies investigating the impact of the SARS-CoV-2 on the CNS and mental health outcomes. We describe neurobiology of the virus, highlighting the relevance to mental disorders. Furthermore, this article summarizes the impact of the SARS-CoV-2 from the public health perspective. Finally, we present a critical appraisal of evidence and indicate future directions for studies in this field.


Assuntos
Infecções por Coronavirus/psicologia , Transtornos Mentais/psicologia , Saúde Mental , Pneumonia Viral/psicologia , Betacoronavirus , Encéfalo/virologia , Infecções por Coronavirus/complicações , Humanos , Transtornos Mentais/complicações , Transtornos Mentais/etiologia , Doenças do Sistema Nervoso/etiologia , Pandemias , Pneumonia Viral/complicações , Resultado do Tratamento
2.
Curr Opin Ophthalmol ; 31(6): 495-502, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33009082

RESUMO

PURPOSE OF REVIEW: This review discusses general features and organ-specific presentations of Susac syndrome as well as diagnosis and treatment. RECENT FINDINGS: Latest literature regarding demographics, new diagnostic modalities such as optical coherence tomography and treatment options for Susac syndrome are discussed in detail in this review, summarizing the most recent updated information. SUMMARY: Susac syndrome is a rare, underdiagnosed, and often misdiagnosed disease that can lead to severe complications such as deafness, vision loss, dementia, and death. It involves the central nervous system and may mimic other neurological and neuro-ophthalmological diseases.


Assuntos
Síndrome de Susac , Transtornos da Visão/etiologia , Encéfalo , Humanos , Síndrome de Susac/complicações , Síndrome de Susac/diagnóstico , Síndrome de Susac/terapia , Tomografia de Coerência Óptica , Transtornos da Visão/epidemiologia
3.
Zh Nevrol Psikhiatr Im S S Korsakova ; 120(8. Vyp. 2): 24-29, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33016673

RESUMO

OBJECTIVE: To identify the likelihood of developing systemic inflammation (SI) as a general pathological process in severe haemorrhagic intracerebral stroke with and without the phenomenon of ineffective cerebral blood flow. MATERIAL AND METHOD: Three groups were examined: 1) 89 blood donors (controls), 2) 15 patients with severe haemorrhagic stroke without the phenomenon of ineffective brain blood flow; 3) 26 patients with severe haemorrhagic stroke with ineffective cerebral blood flow. Ineffective cerebral blood circulation was recorded on the basis of transcranial Doppler ultrasound data; 87% of patients had clinical signs of brain death. All patients in the groups with haemorrhagic stroke had signs of multiple organ dysfunction according to the Sepsis-related Organ Failure scale, all of them received intensive care. An integrated scale based on the determination of plasma concentrations of cytokines (IL-6, IL-8, IL-10, TNF-α), procalcitonin, cortisol, D-dimers, myoglobin, troponin I was used to verify systemic inflammation. RESULTS AND CONCLUSION: Systemic inflammation or borderline state (pre-SI) was identified in all patients of the second group both on 1-3 days from the onset of haemorrhagic stroke, and on 5-8 days. On the contrary, in the third group, there were no signs of SI on 1-3 days. On 5-8 days, signs of SI and pre-SI were recorded only in 18.2% of patients. Apparently, the reason for these differences is the blockade of the passage of tissue decay products and other pro-inflammatory factors into the bloodstream from the damaged brain in the third group.


Assuntos
Circulação Cerebrovascular , Hemorragias Intracranianas/complicações , Hemorragias Intracranianas/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Encéfalo/diagnóstico por imagem , Humanos , Inflamação
4.
Zh Nevrol Psikhiatr Im S S Korsakova ; 120(8. Vyp. 2): 30-36, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33016674

RESUMO

BACKGROUND: The issue of the diagnostic significance and clinical value of neuron-specific enolase (NSE) and brain-derived neurotropic factor (BDNF) in the acute period of stroke remains controversial. Therefore, it is advisable to study the correlation of biomarkers with the clinical characteristics of stroke in the time period of early recovery. OBJECTIVE: To monitor NSE and BDNF levels in peripheral blood, to analyze the clinical and laboratory correlations in patients with ischemic stroke at the stages of medical rehabilitation in the early recovery period. MATERIAL AND METHODS: Forty-nine patients with ischemic stroke in the middle cerebral artery were examined. The observation period is 90 days. Observation Points are Day 1; Day 14; Day 45; Day 90. The National Institute of Health Stroke Scale (NIHSS), the Fugle-Meyer Scale (FMA), the Modified Rankin Scale (mRS) were administered. NSE was determined in blood serum by enzyme-linked immunosorbent assay, BDNF was analyzed on a multiplex analyzer. RESULTS AND CONCLUSION: NSEDay1 in patients was significantly higher than in the comparison group (pDay1-comparison group<0.001) with a trend to a maximum decrease on the 90th day of stroke (pDay1-90<0.001). BDNFDay1 turned out to be lower than in the comparison group (pDay1-comparison group=0.006) and significantly increased by the 14th day of the stroke (pDay1-14<0.001; pDay14-comparison group=0.637). A negative correlation was found between a decrease in NSEDay14 and an increase in BDNFDay14 (r= -0.349; p=0.05). A positive correlation was found between an increase in BDNFDay14 and a decrease in mRS scores Day90 (r=0.499, p=0.035). Outcomes in patients in group 1 (after stages I and II of rehabilitation) on the assessment scales were significantly better than in patients discharged after stage I for outpatient monitoring - group 2 (p<0.05). In group 1, BDNFDay90 did not differ from BDNFDay14 (pDay14-90-Group1=0.17), and in group 2 it was significantly lower by the end of the early recovery period (pDay14-90-Group2=0.002).


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Encéfalo , Fator Neurotrófico Derivado do Encéfalo , Humanos , Fosfopiruvato Hidratase , Reabilitação do Acidente Vascular Cerebral
5.
Artigo em Chinês | MEDLINE | ID: mdl-33040499

RESUMO

Objective:To analyze the correlation of the degree of affective disorder and brain function changes by comparing the differences of resting-state functional Magnetic Resonance Imaging(rs-fMRI) between healthy volunteers without tinnitus and patients with tinnitus. Method:A analysis of 19 patients with tinnitus and 15 healthy volunteers without tinnitus. The patients were divided into mild group and severe group according to tinnitus handicap inventory(THI). Rs-fMRI was collected and the regional homogeneity(ReHo) analysis, amplitude of low-frequency fluctuation(ALFF) analysis, and fractional amplitude of low frequency fluctuation(fALFF) analysis of rs-fMRI were performed by DPABI software. Two-sample t-test of the ReHo value, ALFF value and fALFF value between the mild group and the control group, the severe group and the control group, were performed respectively. Result:The fALFF value of the left occipital gyrus in the mild group was higher than that in the control group, the difference was statistically significant(P<0.05), but there is no statistically significant difference of ALFF value and ReHo value between two groups. The ALFF value of the middle temporal gyrus(left), superior frontal gyrus(right), inferior frontal gyrus pars triangularis(left) and caudate nucleus(left) in the severe group were higher than those of the control group. But there was no significant difference in the fALFF value and the ReHo value. Conclusion:Different severity of affective disorder in patients with tinnitus have different areas of brain function abnormalities. Mild group was detected by fALFF analysis and the active brain area was the left middle occipital region. Severe group was detected by ALFF analysis. The active brain regions were left middle temporal gyrus, right superior frontal gyrus, left inferior frontal gyrus pars triangularis, and left caudate nucleus.


Assuntos
Zumbido , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imagem por Ressonância Magnética , Transtornos do Humor , Zumbido/diagnóstico por imagem
6.
Yakugaku Zasshi ; 140(10): 1207-1212, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32999199

RESUMO

T-type calcium channels are low-threshold voltage-gated calcium channel and characterized by unique electrophysiological properties such as fast inactivation and slow deactivation kinetics. All subtypes of T-type calcium channel (Cav3.1, 3.2 and 3.3) are widely expressed in the central nerve system, and they have an important role in homeostasis of sleep, pain response, and development of epilepsy. Recently, several reports suggest that T-type calcium channels may mediate neuronal plasticity in the mouse brain. We succeeded to develop T-type calcium channel enhancer ethyl 8'-methyl-2',4-dioxo-2-(piperidin-1-yl)-2'H-spiro[cyclopentane-1,3'-imidazo[1,2-a]pyridine]-2-ene-3-carboxylate (SAK3) which enhances Cav3.1 and 3.3 currents in each-channel expressed neuro2A cells. SAK3 can promote acetylcholine (ACh) release in the mouse hippocampus via enhancing T-type calcium channel. In this review, we have introduced the role of T-type calcium channel, especially Cav3.1 channel in the mouse hippocampus based on our previous data using SAK3 and Cav3.1 knockout mice.


Assuntos
Canais de Cálcio Tipo T/efeitos dos fármacos , Canais de Cálcio Tipo T/fisiologia , Imidazóis/farmacologia , Neurônios/fisiologia , Compostos de Espiro/farmacologia , Acetilcolina/metabolismo , Animais , Encéfalo/fisiologia , Canais de Cálcio Tipo T/genética , Canais de Cálcio Tipo T/metabolismo , Células Cultivadas , Sistema Nervoso Central/metabolismo , Fenômenos Eletrofisiológicos , Epilepsia/etiologia , Expressão Gênica/efeitos dos fármacos , Hipocampo/metabolismo , Homeostase , Camundongos , Plasticidade Neuronal , Dor/etiologia , Ratos , Sono/fisiologia
7.
Yakugaku Zasshi ; 140(10): 1235-1242, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32999202

RESUMO

The central nervous system (CNS) is segregated from the circulating blood and peripheral tissues by endothelial and epithelial barriers. To overcome refractory CNS diseases, it is important to understand the membrane transport systems of drugs and the endogenous compounds that relate to the pathogenesis of CNS diseases at these barriers. The endothelial barrier in the brain is the blood-brain barrier (BBB). Our studies clarified the efflux transport of prostaglandin E2 (PGE2), a modulator of neural excitation and inflammatory responses, across the BBB via plasma membrane transporters such as organic anion transporter 3 (Oat3) and multidrug resistance-associated protein 4 (Mrp4). This efflux transport was attenuated by peripheral inflammation or cerebral treatment with neuroexcitatory l-glutamate, suggesting that BBB-mediated PGE2 elimination was altered under several pathological conditions. We also examined excitatory amino acid transporter (EAAT) 1 and 3 as l-glutamate efflux transporters of the inner blood-retinal barrier (BRB) and blood-cerebrospinal barrier. It was considered that these efflux membrane transporters participated in the homeostasis of neuroexcitatory and neuroinflammatory responses in the brain and retina. Moreover, we identified connexin 43 (Cx43) hemichannels as a new membrane transport system that is activated under pathological conditions and recognizes several monocarboxylate drugs, such as valproate. As it is expected that the action of these membrane transporters across the CNS barriers is of great importance in understanding the pathology of various neuroexcitatory diseases, our studies should contribute to the establishment of therapeutic strategies for refractory CNS diseases.


Assuntos
Transporte Biológico , Barreira Hematoencefálica/metabolismo , Barreira Hematorretiniana/metabolismo , Encéfalo/metabolismo , Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/metabolismo , Desenvolvimento de Medicamentos , Proteínas de Membrana Transportadoras/metabolismo , Retina/metabolismo , Animais , Doenças do Sistema Nervoso Central/tratamento farmacológico , Conexina 43/metabolismo , Dinoprostona/metabolismo , Transportador 1 de Aminoácido Excitatório/metabolismo , Ácido Glutâmico/metabolismo , Humanos , Camundongos , Terapia de Alvo Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo
8.
Phys Rev Lett ; 125(12): 128102, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016724

RESUMO

Neurodegenerative diseases, such as Alzheimer's or Parkinson's disease, show characteristic degradation of structural brain networks. This degradation eventually leads to changes in the network dynamics and degradation of cognitive functions. Here, we model the progression in terms of coupled physical processes: The accumulation of toxic proteins, given by a nonlinear reaction-diffusion transport process, yields an evolving brain connectome characterized by weighted edges on which a neuronal-mass model evolves. The progression of the brain functions can be tested by simulating the resting-state activity on the evolving brain network. We show that while the evolution of edge weights plays a minor role in the overall progression of the disease, dynamic biomarkers predict a transition over a period of 10 years associated with strong cognitive decline.


Assuntos
Demência/patologia , Modelos Neurológicos , Doenças Neurodegenerativas/patologia , Animais , Relógios Biológicos , Encéfalo/patologia , Encéfalo/fisiopatologia , Morte Celular/fisiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Conectoma/métodos , Demência/fisiopatologia , Humanos , Camundongos , Doenças Neurodegenerativas/fisiopatologia , Neurônios/patologia
9.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(5): 959-963, 2020 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-33047737

RESUMO

OBJECTIVE: To improve the methods to synthesize and purify of optical-magnetic bimodal molecular probe of Gd-[4, 7-Bis-carboxymethyl-10-(2-fluorescein thioureaethyl)-1, 4, 7, 10-tetraaza-cyclododec-1-yl]-acetic acid complexes. METHODS: Target compound (7), optical-magnetic bimodal molecular molecular probe, was synthesized by the use of 1, 4, 7, 10-tetraazacyclododecane (1) as starting material via substitution reaction, hydrolysis reaction, coupling reaction and complexation reaction with metal. RESULTS: The synthetic route of Gd-[4, 7-Bis-carboxymethyl-10-(2-fluoresceinthioureaethyl)-1, 4, 7, 10-tetraaza-cyclododec-1-yl]-acetic acid complexes was improved. The optical-magnetic bimodal molecular probes were synthesized by substitution reaction, hydrolysis reaction, coupling reaction and complex reaction with metal respectively. For the improved route, the total yield could reach 34.6% which was higher than the original route (18.0%). The structures of those compounds were identified by 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, and mass spectrometry. The improved route could avoid the uncontrollable disadvantage of the substitution reaction, this process could reduce the formation of impurities and made the purification process easier, and in the aspect of purification and separation, the preparative high-performance liquid chromatography with less sample loading and high cost was improved to a column chromatography with many sample loads and being easy to operate. Therefore, the use of column chromatography could be more conducive to mass production of the optical-magnetic bimodal molecular molecular probe. CONCLUSION: The improved synthetic route improves the controllability of the reaction conditions and makes it easier to purify and separate the compounds. At the same time, the improved synthetic route can increase the total yield significantly. The optical-magnetic bimodal molecular probe can combine the living magnetic resonance imaging with the in vitro optical imaging to realize the dual synchronous detection of magneto-optics, so that the detection results of the living magnetic resonance imaging and the in vitro optical imaging are mutually verified. In other words, this synthetic optical-magnetic bimodal molecular probe will make the experimental results more accurate and reliable. In subsequent biological experimental studies, the optical-magnetic bimodal molecular probe can be applied to related research of brain structure and function, and the probe can be used for the brain-related diseases researches, such as brain tumors. after intravenous administration, and thus the optical-magnetic bimodal molecular probe can play an important role in medical treatment of brain tumors and cerebrovascular diseases.


Assuntos
Ácido Acético , Imagem por Ressonância Magnética , Encéfalo , Espectroscopia de Ressonância Magnética , Sondas Moleculares
10.
Arch Pathol Lab Med ; 144(10): 1162-1163, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002155
12.
Nat Commun ; 11(1): 5073, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033238

RESUMO

Brain cells continuously produce and release protons into the extracellular space, with the rate of acid production corresponding to the levels of neuronal activity and metabolism. Efficient buffering and removal of excess H+ is essential for brain function, not least because all the electrogenic and biochemical machinery of synaptic transmission is highly sensitive to changes in pH. Here, we describe an astroglial mechanism that contributes to the protection of the brain milieu from acidification. In vivo and in vitro experiments conducted in rodent models show that at least one third of all astrocytes release bicarbonate to buffer extracellular H+ loads associated with increases in neuronal activity. The underlying signalling mechanism involves activity-dependent release of ATP triggering bicarbonate secretion by astrocytes via activation of metabotropic P2Y1 receptors, recruitment of phospholipase C, release of Ca2+ from the internal stores, and facilitated outward HCO3- transport by the electrogenic sodium bicarbonate cotransporter 1, NBCe1. These results show that astrocytes maintain local brain extracellular pH homeostasis via a neuronal activity-dependent release of bicarbonate. The data provide evidence of another important metabolic housekeeping function of these glial cells.


Assuntos
Astrócitos/metabolismo , Bicarbonatos/metabolismo , Encéfalo/metabolismo , Espaço Extracelular/metabolismo , Acetazolamida/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Anidrases Carbônicas/metabolismo , Células Cultivadas , Estimulação Elétrica , Fluorescência , Hipocampo/metabolismo , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos C57BL , Modelos Biológicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Antagonistas Purinérgicos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Receptores Purinérgicos/metabolismo , Transdução de Sinais , Simportadores de Sódio-Bicarbonato/metabolismo
13.
Rev Prat ; 70(6): 621-625, 2020 Jun.
Artigo em Francês | MEDLINE | ID: mdl-33058602

RESUMO

Acute stroke imaging. Imaging, within the first 24 hours of stroke, supports its clinical diagnosis and allows a careful patient selection for treatment. It excludes hemorrhage and stroke mimics, provides an estimate of potentially salvageable brain tissue, locates and characterizes the intra-arterial thrombus before treatment decision in acute ischaemic stroke. In cerebral hemorrhage, it plays a pivotal role in establishing the diagnosis and identifying causes and complications. We outline the role of neuroimaging applied to patients presenting with acute stroke within the first 24 hours.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Encéfalo , Hemorragia Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/diagnóstico por imagem , Terapia Trombolítica
14.
Artigo em Inglês | MEDLINE | ID: mdl-33017923

RESUMO

This study had two main objectives: (i) to study the effects of volume conduction on different connectivity metrics (Amplitude Envelope Correlation AEC, Phase Lag Index PLI, and Magnitude Squared Coherence MSCOH), comparing the coupling patterns at electrode- and sensor-level; and (ii) to characterize spontaneous EEG activity during different stages of Alzheimer's disease (AD) continuum by means of three complementary network parameters: node degree (k), characteristic path length (L), and clustering coefficient (C). Our results revealed that PLI and AEC are weakly influenced by volume conduction compared to MSCOH, but they are not immune to it. Furthermore, network parameters obtained from PLI showed that AD continuum is characterized by an increase in L and C in low frequency bands, suggesting lower integration and higher segregation as the disease progresses. These network changes reflect the abnormalities during AD continuum and are mainly due to neuronal alterations, because PLI is slightly affected by volume conduction effects.


Assuntos
Doença de Alzheimer , Benchmarking , Encéfalo , Eletroencefalografia , Humanos , Rede Nervosa
15.
Artigo em Inglês | MEDLINE | ID: mdl-33017925

RESUMO

It is a hot research direction to reveal the working mechanism of brain by measuring the connection characteristics of brain function network. In this paper, to decode pigeon behavior outcomes in goal-directed decision task, an experiment based on plus maze was designed and the nidopallium caudolaterale (NCL) of the pigeon was selected as the target brain region. The local field potential (LFP) signals in the waiting area (WA) and turning area (TA) were recorded when the pigeons performed the goal-directed tasks. Then, the brain functional connection networks of the LFPs were constructed and the extracted features were applied to decode pigeon behavior outcomes. Firstly, continuous wavelet transform (CWT) was used to carried out time-frequency analysis and the task-related frequency band (40-60 Hz) was extracted. Then, weighted sparse representation (WSR) method was used to construct the functional connectivity network and the related network features were selected. Finally, k-nearest neighbor (kNN) algorithm was used to decode behavior outcomes. The results show that the energy difference between TA and WA in 40-60 Hz band is significantly higher than those in other bands. The selected features have good discriminability for the representation of the differences between WA and TA. The decoding results also suggest the classification performance of the different behavior outcomes. These results show the effectiveness of the WSR to construct the function network to decode behavior outcomes.


Assuntos
Columbidae , Objetivos , Algoritmos , Animais , Encéfalo , Condicionamento Operante
16.
Artigo em Inglês | MEDLINE | ID: mdl-33017926

RESUMO

The study of working memory (WM) is a hot topic in recent years and accumulating literatures underlying the achievement and neural mechanism of WM. However, the effect of WM training on cognitive functions were rarely studied. In this study, nineteen healthy young subjects participated in a longitudinal design with one week N-back training (N=1,2,3,4). Experimental results demonstrated that training procedure could help the subjects master more complex psychological tasks when comparing the pre-training performance with those post-training. More specifically, the behavior accuracy increased from 68.14±9.34%, 45.09±14.90%, 39.12±12.71%, and 32.11±10.98% for 1-back, 2-back, 3-back and 4-back respectively to 73.52±4.01%, 69.14±5.28%, 69.09±6.41% and 64.41±5.12% after training. Furthermore, we applied electroencephalogram (EEG) power and functional connectivity to reveal the neural mechanisms of this beneficial effect and found that the EEG power of δ, θ and α band located in the left temporal and occipital lobe increased significantly. Meanwhile, the functional connectivity strength also increased obviously in δ and θ band. In sum, we showed positive effect of WM training on psychological performance and explored the neural mechanisms. Our findings may have the implications for enhancing the performance of participants who are prone to cognitive.


Assuntos
Encéfalo , Memória de Curto Prazo , Eletroencefalografia , Humanos , Aprendizagem , Lobo Occipital
17.
Artigo em Inglês | MEDLINE | ID: mdl-33017928

RESUMO

Transient electrophysiological anomalies in the human brain have been associated with neurological disorders such as epilepsy, may signal impending adverse events (e.g, seizurse), or may reflect the effects of a stressor, such as insufficient sleep. These, typically brief, high-frequency and heterogeneous signal anomalies remain poorly understood, particularly at long time scales, and their morphology and variability have not been systematically characterized. In continuous neural recordings, their inherent sparsity, short duration and low amplitude makes their detection and classification difficult. In turn, this limits their evaluation as potential biomarkers of abnormal neurodynamic processes (e.g., ictogenesis) and predictors of impending adverse events. A novel algorithm is presented that leverages the inherent sparsity of high-frequency abnormalities in neural signals recorded at the scalp and uses spectral clustering to classify them in very high-dimensional signals spanning several days. It is shown that estimated clusters vary dynamically with time and their distribution changes substantially both as a function of time and space.


Assuntos
Encéfalo , Epilepsia , Algoritmos , Análise por Conglomerados , Fenômenos Eletrofisiológicos , Epilepsia/diagnóstico , Humanos
18.
Artigo em Inglês | MEDLINE | ID: mdl-33017931

RESUMO

Affective personality traits have been associated with a risk of developing mental and cognitive disorders and can be informative for early detection and management of such disorders. However, conventional personality trait detection is often biased and unreliable, as it depends on the honesty of the subjects when filling out the lengthy questionnaires. In this paper, we propose a method for objective detection of personality traits using physiological signals. Subjects are shown affective images and videos to evoke a range of emotions. The electrical activity of the brain is captured using EEG during this process and the multi-channel EEG data is processed to compute the inter-hemispheric asynchrony of the brainwaves. The most discriminative features are selected and then used to build a machine learning classifier, which is trained to predict 16 personality traits. Our results show high predictive accuracy for both image and video stimuli individually, and an improvement when the two stimuli are combined, achieving a 95.49% accuracy. Most of the selected discriminative features were found to be extracted from the alpha frequency band. Our work shows that personality traits can be accurately detected with EEG data, suggesting possible use in practical applications for early detection of mental and cognitive disorders.


Assuntos
Ondas Encefálicas , Eletroencefalografia , Encéfalo/diagnóstico por imagem , Aprendizado de Máquina , Personalidade
19.
Artigo em Inglês | MEDLINE | ID: mdl-33017939

RESUMO

Electroencephalography (EEG) is a commonly used method for monitoring brain activity. Automating an EEG signal processing pipeline is imperative to the exploration of real-time brain computer interface (BCI) applications. EEG analysis demands substantial training and time for removal of distinct unwanted independent components (ICs), generated via independent component analysis, corresponding to artifacts. The considerable subject-wise variations across these components motivates defining a procedural way to identify and eliminate these artifacts. We propose DeepIC-virtual, a convolutional neural network (CNN) deep learning classifier to automatically identify brain components in the ICs extracted from the subject's EEG data gathered while they are being immersed in a virtual reality (VR) environment. This work examined the feasibility of DL techniques to provide automated ICs classification on noisy and visually engaging upright stance EEG data. We collected the EEG data for six subjects while they were standing upright in a VR testing setup simulating pseudo-randomized variations in height and depth conditions and induced perturbations. An extensive 1432 IC representation images data set was generated and manually labelled via an expert as brain components or one of the six distinct removable artifacts. The supervised CNN architecture was utilized to categorize good brain ICs and bad artifactual ICs via generated images of topographical maps. Our model categorizing good versus bad IC topographical maps resulted in a binary classification accuracy and area under curve of 89.20% and 0.93 respectively. Despite significant imbalance, only 1 out of the 57 present brain ICs in the withheld testing set was miss-classified as an artifact. These results will hopefully encourage clinicians to integrate BCI methods and neurofeedback to control anxiety and provide a treatment of acrophobia, given the viability of automatic classification of artifactual ICs.


Assuntos
Algoritmos , Aprendizado Profundo , Encéfalo , Eletroencefalografia , Processamento de Sinais Assistido por Computador
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 104-107, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33017941

RESUMO

EEG monitoring of early brain function and development in neonatal intensive care units may help to identify infants with high risk of serious neurological impairment and to assess brain maturation for evaluation of neurodevelopmental progress. Automated analysis of EEG data makes continuous evaluation of brain activity fast and accessible. A convolutional neural network (CNN) for regression of EEG maturational age of premature neonates from marginally preprocessed serial EEG recordings is proposed. The CNN was trained and validated using 141 EEG recordings from 43 preterm neonates born below 28 weeks of gestation with normal neurodevelop-mental outcome at 12 months of corrected age. The estimated functional brain maturation between the first and last EEG recording increased in each patient. On average over 96% of repeated measures within an infant had an increasing EEG maturational age according to the post menstrual age at EEG recording time. Our algorithm has potential to be deployed to support neonatologists for accurate estimation of functional brain maturity in premature neonates.


Assuntos
Eletroencefalografia , Recém-Nascido Prematuro , Encéfalo , Aprendizado Profundo , Feminino , Humanos , Lactente , Recém-Nascido , Redes Neurais de Computação , Gravidez
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