Research on electroencephalogram power spectral density of stroke patients under transcranial direct current stimulation / 生物医学工程学杂志

Transcranial direct current stimulation (tDCS) has become a new method of post-stroke rehabilitation treatment and is gradually accepted by people. However, the neurophysiological mechanism of tDCS in the treatment of stroke still needs further study. In this study, we recruited 30 stroke patients with damage to the left side of the brain and randomly divided them into a real tDCS group (15 cases) and a sham tDCS group (15 cases). The resting EEG signals of the two groups of subjects before and after stimulation were collected, then the difference of power spectral density was analyzed and compared in the band of delta, theta, alpha and beta, and the delta/alpha power ratio (DAR) was calculated. The results showed that after real tDCS, delta band energy decreased significantly in the left temporal lobes, and the difference was statistically significant ( P < 0.05); alpha band energy enhanced significantly in the occipital lobes, and the difference was statistically significant ( P < 0.05); the difference of theta and beta band energy was not statistically significant in the whole brain region ( P > 0.05). Furthermore, the difference of delta, theta, alpha and beta band energy was not statistically significant after sham tDCS ( P > 0.05). On the other hand, the DAR value of stroke patients decreased significantly after real tDCS, and the difference was statistically significant ( P < 0.05), and there was no significant difference in sham tDCS ( P > 0.05). This study reveals to a certain extent the neurophysiological mechanism of tDCS in the treatment of stroke.

Oscilopatología en Trastornos del Espectro Autista / Oscillopathology in Autist Spectrum Disorder

Language as a vehicle for human development has an important impact on social processes which are decisive in the establishment of optimal living conditions. Modern studies have found that skills that make of language an activity of complex multisensory integration are determined by the oscillation rhythms of the different brain waves described from neurosciences. In the literature has described an abnormal pattern of oscillations, responsible for communicative deficiencies in individuals with Autist Spectrum Disorders and beside with social deficits, resulting in a typically characteristic profile. Brain waves show an impact on the mental states that be high cognitive demand as learning, communication and speech understanding, widespread difficulties in this population. The recent findings presented here and product of a judicious bibliographic review, are characterized within speech therapy making it possible to land the intervention processes to the linguistic and cognitive needs of these individuals, using biological mechanisms and resulting in possible procedures of greater relevance and effectiveness, that improve user's life quality and motivate speech therapy and similar professionals to expand their knowledge in this interesting field.

Basics of Electroencephalography for Neuropsychiatrist / 신경정신의학

In 1924, Hans Berger, a German psychiatrist, recorded the brain waves from a human brain for the first time. Many advances have been made in this field since then. Currently, brain waves are generated by a variety of computer technologies, including brain computer interface technology, and robot or artificial intelligence technology has also made amazing progress. A mental health practitioner who deals with brain-related medicine has an obligation and responsibility to research and find clinical applications of brain waves because they contain a great deal of information hidden in the brain. Therefore, understanding the basics of electroencephalography will contribute to a determination and resolution of various clinical situations. This review discusses basic knowledge before dealing with brain waves. In addition to a visual inspection of general brain waves, quantitative analysis of brain waves is expected to become an important area of interest for mental health practitioners.

Altered Local Field Potential Relationship Between the Parafascicular Thalamic Nucleus and Dorsal Striatum in Hemiparkinsonian Rats / 神经科学通报·英文版

The thalamostriatal pathway is implicated in Parkinson's disease (PD); however, PD-related changes in the relationship between oscillatory activity in the centromedian-parafascicular complex (CM/Pf, or the Pf in rodents) and the dorsal striatum (DS) remain unclear. Therefore, we simultaneously recorded local field potentials (LFPs) in both the Pf and DS of hemiparkinsonian and control rats during epochs of rest or treadmill walking. The dopamine-lesioned rats showed increased LFP power in the beta band (12 Hz-35 Hz) in the Pf and DS during both epochs, but decreased LFP power in the delta (0.5 Hz-3 Hz) band in the Pf during rest epochs and in the DS during both epochs, compared to control rats. In addition, exaggerated low gamma (35 Hz-70 Hz) oscillations after dopamine loss were restricted to the Pf regardless of the behavioral state. Furthermore, enhanced synchronization of LFP oscillations was found between the Pf and DS after the dopamine lesion. Significant increases occurred in the mean coherence in both theta (3 Hz-7 Hz) and beta bands, and a significant increase was also noted in the phase coherence in the beta band between the Pf and DS during rest epochs. During the treadmill walking epochs, significant increases were found in both the alpha (7 Hz-12 Hz) and beta bands for two coherence measures. Collectively, dramatic changes in the relative LFP power and coherence in the thalamostriatal pathway may underlie the dysfunction of the basal ganglia-thalamocortical network circuits in PD, contributing to some of the motor and non-motor symptoms of the disease.

Isolated effective coherence analysis of epileptogenic networks in temporal lobe epilepsy using stereo-electroencephalography / 生物医学工程学杂志

Stereo-electroencephalography (SEEG) is widely used to record the electrical activity of patients' brain in clinical. The SEEG-based epileptogenic network can better describe the origin and the spreading of seizures, which makes it an important measure to localize epileptogenic zone (EZ). SEEG data from six patients with refractory epilepsy are used in this study. Five of them are with temporal lobe epilepsy, and the other is with extratemporal lobe epilepsy. The node outflow (out-degree) and inflow (in-degree) of information are calculated in each node of epileptic network, and the overlay between selected nodes and resected nodes is analyzed. In this study, SEEG data is transformed to bipolar montage, and then the epileptic network is established by using independent effective coherence (iCoh) method. The SEEG segments at onset, middle and termination of seizures in Delta, Theta, Alpha, Beta, and Gamma rhythms are used respectively. Finally, the K-means clustering algorithm is applied on the node values of out-degree and in-degree respectively. The nodes in the cluster with high value are compared with the resected regions. The final results show that the accuracy of selected nodes in resected region in the Delta, Alpha and Beta rhythm are 0.90, 0.88 and 0.89 based on out-degree values in temporal lobe epilepsy patients respectively, while the in-degree values cannot differentiate them. In contrast, the out-degree values are higher outside the temporal lobe in the patient with extratemporal lobe epilepsy. Based on the out-degree feature in low-frequency epileptic network, this study provides a potential quantitative measure for identifying patients with temporal lobe epilepsy in clinical.

Electroencephalographic Changes Induced by a Neurofeedback Training : A Preliminary Study in Primary Insomniac Patients / 수면정신생리

OBJECTIVES: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. METHODS: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. RESULTS: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session (13.9 ± 2.6 vs. 12.2 ± 3.8 and 3.6 ± 0.9 vs. 3.2 ± 1.0 in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. CONCLUSION: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.

Children with ADHD shown different alpha, beta and SMR EEG bands during habil motor tasks with high attention demand / Crianças com TDAH exibem diferente perfil no EEG durante tarefas motoras que demandam atenção / Niños con TDAH exhiben diferente perfil de EEG durante tareas motoras que demandan atención

INTRODUCTION: ADHD probably affects more than 50% of schoolchildren, yet although characteristics such as inattention and/or hyperactivity and impulsiveness are clear, electrophysiological brain behavior during motor activity is not fully understood. OBJECTIVE: To investigate alpha, beta, and SMR band patterns on the EEG in children with Attention Deficit Hyperactivity Disorder (ADHD) during attention-demanding motor skills tasks. METHODS: Fourteen children with a mean age of 9.64±1.74 years divided into diagnosed and undiagnosed with ADHD underwent an EEG at rest and during task performance with attentional demand. Alpha, SMR and beta waves were observed on the EEG. Data were evaluated using the Shapiro-Wilk test in order to determine data normality. ONE WAY ANOVA and Tukey's post hoc tests were used to determine intragroup and intergroup differences, and the Pearson (r) and Spearman (p) correlations were used to determine correlations. All treatments had a significance of 5%. RESULTS: The ADHD and N-ADHD groups showed no difference in cortical alpha, beta and SMR bands at rest, but there were differences in cortical behavior during activity. The cortical activity correlation coefficient (0.30) differed from undiagnosed children (0.70). CONCLUSION: The ADHD group had a low correlation coefficient between rest and activity, contrary to the N-ADHD group. In the intergroup comparison, ADHD had higher alpha, beta and SMR band output power during the same high attentional task when compared with N-ADHD. Level of Evidence III.

INTRODUÇÃO: O TDAH afeta, provavelmente, mais de 50% crianças em idade escolar, porém, embora características como falta de atenção e/ou hiperatividade e impulsividade sejam claras, o comportamento eletrofisiológico do cérebro durante atividades motoras não é bem entendido. OBJETIVO: Investigar o padrão das bandas Alfa, Beta e SMR no EEG de crianças com transtorno do déficit de atenção com hiperatividade (TDAH), durante tarefas motrizes com alta demanda de atenção. MÉTODOS: Catorze crianças com média de idade de 9,64 ± 1,74 anos, divididas nos grupos diagnosticadas e não diagnosticadas com TDAH, realizaram EEG em repouso e durante o desempenho de tarefa com demanda de atenção. As ondas Alfa, SMR e Beta foram observadas no EEG. Os dados foram avaliados pelo teste de Shapiro-Wilk para determinar a normalidade dos dados. Os teste ANOVA one-way e post hoc de Tukey foram usados para determinar as diferenças intragrupo e intergrupo, e a correlação de Pearson (r) e Spearman (p) foram usadas para determinar as correlações. Todos os tratamentos tiveram significância de 5%. RESULTADOS: Os grupos TDAH e N-TDAH não apresentaram diferença na banda cortical Alfa, Beta e SMR em repouso, porém, durante a atividade, constataram-se diferenças do comportamento cortical. O índice de correlação da atividade cortical (0,30) foi diferente nas crianças não diagnosticadas (0,70). CONCLUSÃO: O grupo TDAH apresentou baixo índice de correlação entre repouso e atividade, diferentemente do grupo N-TDAH. Na comparação intergrupos, o TDAH apresentou maior potência de saída da banda Alfa, Beta e SMR durante a mesma tarefa de alta atenção em comparação com o N-TDAH. Nível de Evidência III.

INTRODUCCIÓN: El TDAH afecta probablemente a más del 50% de los escolares, pero aunque las características como la falta de atención y/o la hiperactividad e impulsividad sean entendidas como comportamiento electrofisiológico del cerebro durante las actividades motoras, esto no es bien entendido. OBJETIVO: investigar el patrón de las franjas de Alfa, Beta y SMR en el EEG en niños con trastorno de déficit de atención y de Hiperactividad (TDAH), durante tareas motrices con altas demandas de atención. MÉTODOS: catorce niños con promedio de edad de 9,64 ± 1,74 años, divididos en diagnosticados y no diagnosticados con TDAH, realizaron EEG durante el reposo y desempeño de la tarea motriz con alta demanda de atención. Las ondas Alfa, SMR y Beta se observaron en el EEG. Los datos fueron evaluados por el test de Shapiro-Wilk para determinar la normalidad. ANOVA ONE WAY y el test de Tukey fueron utilizados para determinar las diferencias intragrupo e intergrupo, así como también la correlación de Pearson (r) y Spearman (p) fueron usadas para determinar las correlaciones. Todos los tratamientos tuvieron un nivel de significancia del 5%. RESULTADOS: El TDAH y el N-TDAH no presentaron diferencias en la Franja Cortical Alfa, Beta y SMR durante el reposo, no obstante, al estar en actividad, el comportamiento cortical presentó diferencias. El índice de correlación de la actividad cortical (0,30) fue diferente de niños no diagnosticados (0,70). CONCLUSIONES: El TDAH presentó un bajo índice de correlación entre reposo y actividad, a diferencia del N-TDAH. En la comparación intergrupos, el TDAH presentó mayor potencia de salida de la franja Alfa, Beta y SMR durante la misma tarea de alta atención, en comparación con el N-TDAH. Nivel de Evidencia III.

Dendritic Cell Factor 1-Knockout Results in Visual Deficit Through the GABA System in Mouse Primary Visual Cortex / 神经科学通报·英文版

The visual system plays an important role in our daily life. In this study, we found that loss of dendritic cell factor 1 (DCF1) in the primary visual cortex (V1) caused a sight deficit in mice and induced an abnormal increase in glutamic acid decarboxylase 67, an enzyme that catalyzes the decarboxylation of glutamate to gamma aminobutyric acid and CO, particularly in layer 5. In vivo electrophysiological recordings confirmed a decrease in delta, theta, and beta oscillation power in DCF1-knockout mice. This study presents a previously unknown function of DCF1 in V1, suggests an unknown contact between DCF1 and GABA systems, and provides insight into the mechanism and treatment of visual deficits.

Effects of Quantitative Electroencephalography Based Neurofeedback Training on Autonomous Regulations in Patients with Alcohol Use Disorder

PURPOSE: The study investigated whether neurofeedback training (NFT) can normalize the excessive high beta and low alpha waves indicative of hyperarousal and subsequently improve autonomous regulation based on the self-determination theory in alcohol use disorders. METHODS: A nonequivalent control group preteste-posttest design was used. Data were collected using self-report questionnaires from 36 Korean inpatients who met the Alcohol Use Disorder Identification Test in Korea criteria. Data were collected from quantitative electroencephalography to assess alpha (8–12 Hz) and high beta (21–30 Hz) waves for hyperarousal. The questionnaires included Basic Psychological Need Satisfaction scales that assessed autonomy, competence, and relatedness, and the Alcohol Abstinence Self-Efficacy Scale and Treatment Self-Regulation Questionnaire. The experimental group underwent 10 sessions of NFT over 4 weeks. Data were analyzed using the Chi-squared, Manne-Whitney U, and Wilcoxon signed-rank tests. RESULTS: In the experimental group, the alpha wave was increased in 15 of 19 sites and high beta waves were decreased in 15 of 19 sites, but this difference was not significant. However, high beta waves were increased in 15 of 19 sites in the control group, with seven sites (Fz, Cz, Pz, Fp2, F4, C4, and P4) showing significant increases. The experimental group showed a significant increase in basic psychological need satisfaction, alcohol abstinence self-efficacy, and self-regulation compared with the control group. CONCLUSION: NFT is recommended for improving autonomous regulation in alcohol use disorder as a nursing intervention. However, for significantly attenuating hyperarousal through brain wave correction, it may be necessary to increase the number of neurofeedback sessions.

Comparative analysis of the electroencephalogram in patients with Alzheimer's disease, diffuse axonal injury patients and healthy controls using LORETA analysis / Análise comparativa do eletroencefalograma em pacientes com doença de alzheimer, lesão axonal difusa e controles saudáveis: e análise loreta

ABSTRACT Alzheimer's disease (AD) is a dementia that affects a large contingent of the elderly population characterized by the presence of neurofibrillary tangles and senile plaques. Traumatic brain injury (TBI) is a non-degenerative injury caused by an external mechanical force. One of the main causes of TBI is diffuse axonal injury (DAI), promoted by acceleration-deceleration mechanisms. Objective: To understand the electroencephalographic differences in functional mechanisms between AD and DAI groups. Methods: The study included 20 subjects with AD, 19 with DAI and 17 healthy adults submitted to high resolution EEG with 128 channels. Cortical sources of EEG rhythms were estimated by exact low-resolution electromagnetic tomography (eLORETA) analysis. Results: The eLORETA analysis showed that, in comparison to the control (CTL) group, the AD group had increased theta activity in the parietal and frontal lobes and decreased alpha 2 activity in the parietal, frontal, limbic and occipital lobes. In comparison to the CTL group, the DAI group had increased theta activity in the limbic, occipital sublobar and temporal areas. Conclusion: The results suggest that individuals with AD and DAI have impairment of electrical activity in areas important for memory and learning.

RESUMO A dooença de Alzheimer (DA) é uma demência que acomete uma grande parcela da população idosa e caracteriza-se pela presença de emaranhados neurofibrilares e placas senis. O traumatismo cranioencefálico (TCE) é uma lesão não degenerativa causada por uma força mecânica externa. Uma das principais causas de TCE é a lesão axonal difusa (LAD), causada por mecanismos de aceleração-desaceleração. Objetivo: Entender as diferenças dos mecanismos funcionais entre os grupos - DA e LAD do ponto de vista eletroencefalográfico. Métodos: Participaram deste estudo 56 indivíduos adultos. Destes, 20 com DA, 19 com LAD e 17 adultos saudáveis submetidos ao EEG de alta resolução com 128 canais. As fontes corticais dos ritmos do EEG foram estimadas pela análise por tomografia eletromagnética exata de baixa resolução (eLORETA). Resultados: A análise por eLORETA mostrou que, em comparação ao grupo controle (CTL), o grupo DA apresentou aumento da atividade teta nos lobos parietal e frontal e diminuição da atividade alfa 2 nos lobos parietal, frontal, límbico e occipital. Em comparação ao grupo CTL, o grupo LAD apresentou aumento da atividade teta nas áreas límbica, occipital sub-lobar e temporal. Conclusão: Os resultados sugerem que os indivíduos com DA e com LAD apresentam comprometimento da atividade elétrica em áreas importantes para a memória e aprendizagem.

Equilíbrio estático por baropodometria em paciente com ataxia cerebelar após tratamento com neurofeedback / Static balance by baropodometry in patient with cerebellar ataxia post neurofeedback therapy

O Neurofeedback é um aparelho que consegue detectar padrões de ondas cerebrais e redirecioná-los para adequar o equilíbrio e potenciais cerebrais. Vem sendo usado nos últimos anos em atletas e de modo muito raro em quadros neurológicos. Assim, o objetivo desse estudo foi analisar o efeito do Neurofeedback (NFB) em uma criança com Ataxia cerebelar, em uma clínica de Fisioterapia, em Fortaleza/CE. Tratou-se de um relato de caso. Foram realizadas uma avaliação inicial e uma ao final da intervenção com NFB por meio de eletroencefalografia quantitativa. Os dados foram analisados por Baropodometria e Estabilometria, durante 30 segundos, na posição bípede, e 50 segundos na posição sentada. O treino foi realizado para inibição de High Beta. Conclui-se que com a inibição dessa onda, houve diminuição na ansiedade da criança, relaxamento muscular, com consequente melhora no equilíbrio, evidenciada na baropodometria. (AU)

Neurofeedback is a device that can detect brain wave patterns and redirect them to optimize balance and brain potentials and has been used in recent years in athletes and neurological conditions. The aim of this interventional case study was to analyze the effect of Neurofeedback (NFB) in a child with cerebellar ataxia in a Physiotherapy clinic located in the city of Fortaleza/CE. Two evaluations were made, one initial and one final, and the data were analyzed by Baropodometry and Stabilometry, 30 seconds in the biped position, and 50 seconds in the sitting position. The training was done for the inhibition of High Beta. We concluded that with the inhibition of this wave, there was a decrease in the anxiety, promoting a muscle relaxing and better equilibrium. (AU)

Monitoring time of interictal epileptiform discharges by long-term video EEG in patients with epilepsy / 浙江大学学报·医学版

To optimize the monitoring time of interictal epileptiform discharges (IED) in patients with epilepsy by long-term video electroencephalogram (VEEG).The cumulative percentages of IED detected by VEEG in 346 epilepsy patients (349 times) with different purposes, different waking sleep states and different MRI findings were retrospectively analyzed. According to the purposes, there were 164 patients (165 times) for clarifying diagnosis, 124 patients (124 times) for preoperative evaluation and 58 patients (60 times) for adjustment of medications. According to MRI results, there were responsible lesions in 98 patients (98 times) and no responsible lesions in 173 patients (174 times).Among 346 patients (349 times), IED was detected within 24 h in 231 patients (times). The percentage of detection in patients with purpose of preoperative evaluation was higher than those with purpose of diagnosis and medication adjustment. The detection of LED was gradually increased in first 8 h with 59.0%, then stably in 24 h. 46.8% IED was recorded during sleep time, particularly in the second stage of sleep. The cumulative percentage of IED in patients with abnormal MRI findings was higher in all periods. It reached 83.7% within 8 h, and then tended to be stable.The study shows that LED should be monitored by VEEG at least 8 hours and should include the second stage of sleep in patients with epilepsy. Patients with refractory epilepsy and with abnormal lesions on MRI should record IED more frequently.

Comparison of QEEG Findings between Adolescents with Attention Deficit Hyperactivity Disorder (ADHD) without Comorbidity and ADHD Comorbid with Internet Gaming Disorder

Internet gaming disorder (IGD) is often comorbid with attention deficit hyperactivity disorder (ADHD). In this study, we compared the neurobiological differences between ADHD comorbid with IGD (ADHD+IGD group) and ADHD without comorbidity (ADHD-only group) by analyzing quantitative electroencephalogram (QEEG) findings. We recruited 16 male ADHD+IGD, 15 male ADHD-only adolescent patients, and 15 male healthy controls (HC group). Participants were assessed using Young's Internet Addiction Scale and ADHD Rating Scale. Relative power and inter- and intra-hemispheric coherences of brain waves were measured using a digital electroencephalography (EEG) system. Compared to the ADHD-only group, the ADHD+IGD group showed lower relative delta power and greater relative beta power in temporal regions. The relative theta power in frontal regions were higher in ADHD-only group compared to HC group. Inter-hemispheric coherence values for the theta band between F3–F4 and C3–C4 electrodes were higher in ADHD-only group compared to HC group. Intra-hemispheric coherence values for the delta, theta, alpha, and beta bands between P4–O2 electrodes and intra-hemispheric coherence values for the theta band between Fz–Cz and T4–T6 electrodes were higher in ADHD+IGD group compared to ADHD-only group. Adolescents who show greater vulnerability to ADHD seem to continuously play Internet games to unconsciously enhance attentional ability. In turn, relative beta power in attention deficit in ADHD+IGD group may become similar to that in HC group. Repetitive activation of brain reward and working memory systems during continuous gaming may result in an increase in neuronal connectivity within the parieto-occipital and temporal regions for the ADHD+IGD group.

A Preliminary Study on qEEG in Burn Patients With Chronic Pruritus

OBJECTIVE: To explore and determine the reorganizational changes in the cortical neural circuits associated with pruritis, this study was undertaken to compare the electroencephalography (EEG) changes in burn patients having primary symptoms of chronic itching (pruritis) and their paired healthy subjects. METHODS: Eight subjects were recruited for this exploratory pilot study: 4 patients with pruritus after burn injury matched by gender and age with 4 healthy subjects. EEG recordings were analyzed for absolute alpha, low beta, high beta, and theta power for both groups. RESULTS: The mean age of the burn patients was 41.75 years; while the mean age for the matched healthy subjects was 41.5 years. All subjects were male. A decreased alpha activity was observed in the occipital channels (0.82 vs. 1.4; p=0.01) and a decreased low beta activity in the frontal area (0.22 vs. 0.4; p=0.049) in eyes closed conditions. An overall decreased theta trend was observed in both the eyes open and eyes closed conditions in burn patients, compared to healthy individuals. CONCLUSION: This preliminary study presents initial evidence that chronic pruritus in burn subjects may be associated with brain reorganizational changes at the cortical level characterized by an EEG pattern.

Association between clinical condition and F-waves changes in the acute phase of stroke / Associação entre condição clínica e alterações das ondas-F na fase aguda do acidente vascular cerebral

ABSTRACT Objective To relate F-waves with clinical and laboratory exams in the acute phase of stroke. Methods Inclusion criteria for this cross-sectional study were: hemiplegia, absence of previous cranial trauma, myopathy, diabetes, alcoholism or other known causes of peripheral neuropathy, and normal sensory and motor conduction. The National Institutes of Health Stroke Scale (NIHSS) score, glycemia, glucosilate hemoglobin, and CPK were obtained at admission by routine blood exams. After hospital admission, the F-wave latencies and persistence were obtained from the deep peroneal nerve using symmetrical techniques. Results Evaluation of 20 individuals – mean age 66 years, 50% male and 85% Caucasian – showed association of F-wave persistence with glycemia (r = 0.71; p < 0.001) and NIHSS categorized (NIHSS 1-7 = 65.0 x NIHSS 9-23 = 100; p = 0.004). Multivariate analysis found only association of F-wave persistence with glycemia β = 0.59 (0.44–0.74); p < 0.001. Conclusion The increase in the persistence of F-waves are associated with hyperglycemia in the acute phase of stroke.

RESUMO Objetivo Relacionar as ondas-F com exames clínicos e laboratoriais na fase aguda do acidente vascular cerebral (AVC). Os critérios de inclusão para este estudo transversal foram: hemiplegia, ausência de trauma craniano, miopatia, diabetes, alcoolismo ou outra causa conhecida de neuropatia periférica, além de condução sensorial e motora normal. O National Institutes of Health Stroke Scale (NIHSS), glicemia, hemoglobina glicada e CPK foram obtidos na admissão por meio de exames de rotina. Após a admissão hospitalar, a latência e persistência das ondas-F foram obtidas por meio da estimulação do nervo fibular profundo utilizando técnicas simétricas. Foram avaliados 20 indivíduos – média de idade 66 anos, 50% homem e 85% caucasianos – apresentaram associação univariada da persistência das ondas-F com glicemia (r = 0.71; p < 0.001) e NIHSS categorizado (NIHSS 1–7 = 65.0 x NIHSS 9-23 = 100; p = 0.004). Na regressão multivariada foi encontrado associação somente entre persistência de ondas-F com glicemia β = 0.59(0.44–0.74); p < 0.001. Conclusão O aumento da persistência de ondas-F está associado com maior nível de glicemia na fase aguda do AVC.

Neurofeedback: a comprehensive review on system design, methodology and clinical applications

Neurofeedback is a kind of biofeedback, which teaches self-control of brain functions to subjects by measuring brain waves and providing a feedback signal. Neurofeedback usually provides the audio and or video feedback. Positive or negative feedback is produced for desirable or undesirable brain activities, respectively. In this review, we provided clinical and technical information about the following issues: [1] Various neurofeedback treatment protocols i.e. alpha, beta, alpha/theta, delta, gamma, and theta; [2] Different EEG electrode placements i.e. standard recording channels in the frontal, temporal, central, and occipital lobes; [3] Electrode montages [unipolar, bipolar]; [4] Types of neurofeedback i.e. frequency, power, slow cortical potential, functional magnetic resonance imaging, and so on; [5] Clinical applications of neurofeedback i.e. treatment of attention deficit hyperactivity disorder, anxiety, depression, epilepsy, insomnia, drug addiction, schizophrenia, learning disabilities, dyslexia and dyscalculia, autistic spectrum disorders and so on as well as other applications such as pain management, and the improvement of musical and athletic performance; and [6] Neurofeedback softwares. To date, many studies have been conducted on the neurofeedback therapy and its effectiveness on the treatment of many diseases. Neurofeedback, like other treatments, has its own pros and cons. Although it is a non-invasive procedure, its validity has been questioned in terms of conclusive scientific evidence. For example, it is expensive, time-consuming and its benefits are not long-lasting. Also, it might take months to show the desired improvements. Nevertheless, neurofeedback is known as a complementary and alternative treatment of many brain dysfunctions. However, current research does not support conclusive results about its efficacy

Alpha power oscillation in the frontal cortex under Bromazepam and Modafinil effects / Oscilações da potência alfa no córtex frontal sob influência do Bromazepam e Modafinil

ABSTRACTObjective Our aim was to investigate and compare the neuromodulatory effects of bromazepam (6 mg) and modafinil (200 mg) during a sensorimotor task analyzing the changes produced in the absolute alpha power.Method The sample was composed of 15 healthy individuals exposed to three experimental conditions: placebo, modafinil and bromazepam. EEG data were recorded before, during and after the execution of the task. A three-way ANOVA was applied, in order to compare the absolute alpha power among the factors: Group (control, bromazepam and modafinil) Condition (Pre and Post-drug ingestion) and Moment (pre and post-stimulus).Results Interaction was found between the group and condition factors for Fp1, F4 and F3. We observed a main effect of moment and condition for the Fp2, F8 and Fz electrodes.Conclusion We concluded that drugs may interfere in sensorimotor processes, such as in the performance of tasks carried out in an unpredictable scenario.

RESUMOObjetivo Investigar e comparar os efeitos neuromoduladores do bromazepam (6mg) e modafinil (200mg), durante a prática de uma tarefa sensoriomotora, analisando as modificações produzidas na potência absoluta de alfa.Método A amostra foi composta por 15 indivíduos saudáveis, expostos a três condições experimentais: Placebo, modafinil e bromazepam. Dados eletroencefalográficos foram registrados antes, durante e após a execução da tarefa motora. Um ANOVA three-way foi aplicado para comparar a potência absoluta de alfa nos fatores Grupo (controle, bromazepam e modafinil), Condição (Pré e Pós ingestão da droga) e Momento (Pré e Pós estimulo).Resultados Verificou-se interação entre os fatores grupo e condição para os eletrodos Fp1, F4 e F3. Observamos um efeito principal para momento e condição nos eletrodos Fp2, F8 e Fz.Conclusão Concluímos que as drogas, podem interferir em processos sensoriomotores, como no desempenho de tarefas executadas em um cenário imprevisível.

The effects of bromazepam over the central and frontal areas during a motor task: an EEG study / Os efeitos do bromazepam nas áreas corticais central e frontal durante execução de uma tarefa motora: um estudo de EEG

The present study investigates the influence of bromazepam while executing a motor task. Specifically, we intend to analyze the changes in alpha absolute power under two experimental conditions, bromazepam and placebo. We also included analyses of theta and beta frequencies. We collected electroencephalographic data before, during, and after motor task execution. We used a Two Way ANOVA to investigate the condition (PL × Br6 mg) and moment (pre and post) variables for the following electrodes: Fp1, Fp2, F7, F3, Fz, F4, F8, C3, CZ and C4. We found a main effect for condition on the electrodes FP1, F7, F3, Fz, F4, C3 and CZ, for alpha and beta bands. For beta band we also found a main effect for condition on the electrodes Fp2, F8 and C4; for theta band we identified a main effect for condition on C3, Cz and C4 electrodes. This finding suggests that the motor task did not have any influence on the electrocortical activity in alpha, and that the existing modifications were a consequence due merely to the drug use. Despite its anxiolytic and sedative action, bromazepam did not show any significant changes when the individuals executed a finger extension motor task.

O presente estudo investiga a influência do bromazepam durante a execução de uma tarefa motora. Especificamente, pretende-se analisar as mudanças na potência absoluta de alfa sob duas condições experimentais, bromazepam e placebo. Nós também incluímos as analises das frequências teta e beta. Foram coletados dados eletroencefalográficos antes, durante e depois da execução da tarefa motora. Usamos uma Anova de 2 fatores para investigar a condição (PL × Br6 mg) e variáveis no momento (pré e pós) para os seguintes eletrodos: Fp1, Fp2, F7, F3, Fz, F4, F8, C3, C4 e CZ. Encontramos um efeito principal para a condição e eletrodos FP1, F7, F3, Fz, F4, C3 e CZ para alfa e beta. Para beta também foi encontrado um efeito principal para condição nos eletrodos Fp2, F8 e C4; para theta nós identificamos um efeito principal para condition em C3, Cz e C4. Este achado sugere que a tarefa motora não tem qualquer influência sobre a atividade eletrocortical alfa e que as modificações existentes foram uma consequência devido o uso de drogas. Apesar de sua ação ansiolítica e sedativa, o bromazepam não apresentou mudança significativa quando os indivíduos executaram uma tarefa motora.

Bases fisiológicas do eletroencefalograma / Electroencephalogram physiological basis

O principal objetivo deste artigo é descrever as origens fisiológicas do eletroencefalograma (EEG). Para entender isso, é necessário conhecer algumas questões: os geradores neurais e a base celular da atividade elétrica, as interações neuronais e a condutividade dos tecidos através dos quais os potenciais de campo transitarão até serem captados por eletrodos, e a orientação relativa dos geradores com os eletrodos. Assim, são estudados os mecanismos fundamentais dos potenciais de campo extracelulares e a soma da atividade elétrica das populações de neurônios captada fora do sistema nervoso central (SNC) que origina o EEG. Este registra a diferença de voltagem entre locais do cérebro ao longo do tempo.

The main objective of this paper is to describe the physiological origins of the electroencephalogram (EEG). To understand this, it is necessary to know some issues: neural generators and the cellular basis of electrical activity, neuronal interactions and the conductivity of the tissues through which the potentials will travel until they are captured by the electrodes, and the relative orientation of the generators to the electrodes. Therefore, the fundamental mechanisms of extracellular potentials and the sum of the electrical activity of populations of neurons captured outside the central nervous system (CNS) that originate the EEG were studied. The latter records the voltage difference between locations of the brain over time.

Programa Antiestrés de Sincronización Cerebral mediante estimulación visual / Anti-stress software of synchronization of brain wave by visual stimulation

Se presenta un programa computarizado que permite la sincronización de las ondas cerebrales mediante una estimulación visual, a una frecuencia similar a la actividad eléctrica del cerebro en estado de sedación, lo cual favorece la disminución de los niveles de estrés en los pacientes que acuden al Centro de Histoterapia Placentaria para tratar las patologías de Vitiligo, Psoriasis y Alopecia Areata. La aplicación informática fue programada en lenguaje Delphi 7.0 y cuenta con dos módulos para su ejecución. El efecto antiestrés se determinó a través de criterios observacionales y mediante la cuantificación de los niveles de concentración de adrenalina y cortisol en suero sanguíneo(AU)

A computer program that allows synchronization of brain waves by visual stimulation, similar to the electrical activity of the brain in a state of sedation frequently, which helps to reduce stress levels in patients who come to Placental Histotherapy Center to treat Vitiligo, Psoriasis and Alopecia Areata is presented. The computer application was programmed in the language Borland Delphi 7.0 and has two modules for its execution. The anti-stress effect was determined by observational criteria and the cuantification of levels of epinephrine and cortisol concentration in the blood serum(AU)