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The relationship between physical activity and mental health has been widely investigated, and several hypotheses have been formulated about it. Specifically, during the aging process, physical exercise might represent a potential adjunctive treatment for neuropsychiatric disorders and cognitive impairment, helping delay the onset of neurodegenerative processes. Even though exercise itself might act as a stressor, it has been demonstrated that it reduces the harmful effects of other stressors when performed at moderate intensities. Neurotransmitter release, neurotrophic factor and neurogenesis, and cerebral blood flow alteration are some of the concepts involved. In this review, the potential effects of exercise on the aging process and on mental health are discussed, concerning some of the recent findings on animal and human research. The overwhelming evidence present in the literature today suggests that exercise ensures successful brain functioning.

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The EEG has been widely employed in the assessment of electrophysiological changes induced by distinct medications. Its sensibility in detecting alterations produced by a specific substance may be enhanced by methods of quantitative analyses (qEEG). The present study aimed at investigating the modulatory effects of bromazepam on brain dynamics. The effects of bromazepam (3mg) on EEG power distribution were tested in 10 healthy individuals, in a double-blind experiment. The electrophysiological measure was analyzed across experimental conditions, moments, and electrodes, in the delta, theta, alpha and beta frequency bands separately. A significant decrease of relative power was observed in delta and theta (main effect of condition). No interactions were observed. Although the expected anxiolytic EEG profile was not observed (increased beta and decreased alpha activity), this specific result may be related to other factors such as dosage used and the subjects' general physiological state, and not necessarily to the drug itself.

O EEG tem sido amplamente empregado na avaliação de mudanças eletrofisiológicas induzidas por medicações distintas.A sensibilidade desta técnica em detectar alterações produzidas por uma substância pode ser aprimorada por métodos de análise quantitativa (EEGq). O presente estudo teve por objetivo investigar os efeitos modulatórios do bromazepam na dinâmica cerebral. Os efeitos de 3mg de bromazepam na distribuição de potência cortical foram observados em 10 indivíduos sadios, em um desenho duplo-cego. A medida eletrofisiológica foi analisada nas diferentes condições experimentais, momentos e eletrodos, em delta, teta, alfa e beta separadamente. Uma diminuição significativa de potência relativa foi observada em delta e teta (efeito principal para condição). Não foram observadas interações. Embora o perfil ansiolítico do EEG (aumento de beta e diminuição de alfa) não tenha sido observado, esteresultado específico pode estar relacionado a outros fatores, tais como dose utilizada e estado fisiológico dos sujeitos, e não necessariamente à droga propriamente dita.

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The EEG has been widely employed in the assessment of electrophysiological changes induced by distinct medications. Its sensibility in detecting alterations produced by a specific substance may be enhanced by methods of quantitative analyses (qEEG). The present study aimed at investigating the modulatory effects of bromazepam on brain dynamics. The effects of bromazepam (3 mg) on EEG power distribution were tested in 10 healthy individuals, in a double-blind experiment. The electrophysiological measure was analyzed across experimental conditions, moments, and electrodes, in the delta, theta, alpha and beta frequency bands separately. A significant decrease of relative power was observed in delta and theta (main effect of condition). No interactions were observed. Although the expected anxiolytic EEG profile was not observed (increased beta and decreased alpha activity), this specific result may be related to other factors such as dosage used and the subjects' general physiological state, and not necessarily to the drug itself.

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The early stages of visual information processing, involving the detection and perception of simple visual stimuli, have been demonstrated to be sensitive to psychotropic agents. The present study investigated the effects of an acute dose of bromazepam (3 mg), compared with placebo, on the P100 component of the visual evoked potential and reaction time. The sample, consisting of 14 healthy subjects (6 male and 8 female), was submitted to a visual discrimination task, which employed the "oddball" paradigm. Results suggest that bromazepam (3 mg) impairs the initial stage of visual information processing, as observed by an increase in P100 latency.

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The early stages of visual information processing, involving the detection and perception of simple visual stimuli, have been demonstrated to be sensitive to psychotropic agents. The present study investigated the effects of an acute dose of bromazepam (3 mg), compared with placebo, on the P100 component of the visual evoked potential and reaction time. The sample, consisting of 14 healthy subjects (6 male and 8 female), was submitted to a visual discrimination task, which employed the "oddball" paradigm. Results suggest that bromazepam (3 mg) impairs the initial stage of visual information processing, as observed by an increase in P100 latency.

Os estágios iniciais do processamento da informação visual, envolvendo a percepção e detecção de um estímulo visual simples, tem demonstrado serem sensíveis a agentes psicotrópicos. O presente estudo investigou os efeitos de uma dose aguda de bromazepam (3 mg), comparado com placebo, no componente P100 do potencial evocado visual e no tempo de reação. A mostra consistiu de 14 sujeitos sadios (6 homens e 8 mulheres), submetidos a uma tarefa de discriminação visual, a qual empregou o paradigma "oddball". Os resultados sugerem que o bromazepam (3 mg) prejudica o estágio inicial do processamento da informação visual, como observado pelo aumento da latência do P100.

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The aim of the present study was to assess the effects of functional electrical stimulation (FES) on cortical interhemispheric asymmetry. Electrostimulation was performed on the right forearm to stimulate the extension of the index finger. EEG activity was recorded simultaneously. The sample included 45 subjects randomly divided into 3 groups of 15 subjects each: control group (submitted to 24 blocks of stimulation at a null intensity current), group 1 (24 blocks) and group 2 (36 blocks). Interhemispheric asymmetry between F3-F4, C3-C4 and P3-P4 was analyzed through an Anova. Results pointed out to a group x electrode interaction and a general tendency of asymmetry decrease after stimulation.

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O objetivo do presente estudo foi avaliar os efeitos da estimulação elétrica funcional na assimetria cortical inter-hemisférica. Para tal, simultaneamente ao registro da atividade eletroencefalográfica, realizou-se eletroestimulação no antebraço direito para estimulação da extensão do indicador. A amostra consistiu de 45 sujeitos randomizados em 3 grupos de 15 sujeitos cada: grupo controle (submetido a 24 blocos de estimulação com intensidade de corrente zero), grupo 1 (24 blocos) e grupo 2 (36 blocos). A assimetria entre os pares de eletrodos F3-F4, C3-C4 e P3-P4 foi analisada ao longo dos grupos através de uma Anova. Os resultados apontaram para uma interação grupo x eletrodo e uma tendência de diminuição da assimetria inter-hemisférica após a eletroestimulação.

The aim of the present study was to assess the effects of functional electrical stimulation (FES) on cortical interhemispheric asymmetry. Electrostimulation was performed on the right forearm to stimulate the extension of the index finger. EEG activity was recorded simultaneously. The sample included 45 subjects randomly divided into 3 groups of 15 subjects each: control group (submitted to 24 blocks of stimulation at a null intensity current), group 1 (24 blocks) and group 2 (36 blocks). Interhemispheric asymmetry between F3-F4, C3-C4 and P3-P4 was analyzed through an Anova. Results pointed out to a group x electrode interaction and a general tendency of asymmetry decrease after stimulation.

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Benzodiazepines are among the most commonly prescribed medications due to their therapeutic efficacy in reducing anxiety and inducing sleep. Consequently, they have been widely employed in the pharmacological treatment of several disorders. Nevertheless, few studies have analyzed the effects of bromazepam in electroencephalographic activity (EEG). The present study aimed at investigating the modulatory effects of this drug on brain dynamics. Specifically, the effects of bromazepam (3mg) on EEG coherence were tested in a double-blind experiment. The sample, consisting of 10 healthy subjects (5 male and 5 female), was submitted to ten minutes of EEG recording. The electrophysiological measure (coherence) was analyzed across three experimental conditions: bromazepam, placebo 1, and placebo 2. Results indicate that bromazepam significantly increases cortical interhemispheric coherence.

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Benzodiazepines are among the most commonly prescribed medications due to their therapeutic efficacy in reducing anxiety and inducing sleep. Consequently, they have been widely employed in the pharmacological treatment of several disorders. Nevertheless, few studies have analyzed the effects of bromazepam in electroencephalographic activity (EEG). The present study aimed at investigating the modulatory effects of this drug on brain dynamics. Specifically, the effects of bromazepam (3mg) on EEG coherence were tested in a double-blind experiment. The sample, consisting of 10 healthy subjects (5 male and 5 female), was submitted to ten minutes of EEG recording. The electrophysiological measure (coherence) was analyzed across three experimental conditions: bromazepam, placebo 1, and placebo 2. Results indicate that bromazepam significantly increases cortical interhemispheric coherence.

Benzodiazepínicos estão entre as medicações mais comumente prescritas devido à sua eficácia terapêutica para reduzir ansiedade e induzir sono. Conseqüentemente, eles têm sido amplamente empregados no tratamento de diversas desordens. No entanto, poucos estudos têm analisado os efeitos do bromazepam na atividade eletrencefalográfica (EEG). Assim, o presente estudo teve por objetivo investigar os efeitos modulatórios desta droga na dinâmica cerebral. Especificamente, os efeitos de 3 mg de bromazepam na coerência eletrocortical foram analisados em um experimento duplo-cego. A amostra consistiu de 10 sujeitos sadios (5 homens e 5 mulheres), submetidos a dez minutos de captação do sinal de EEG. A medida eletrofisiológica (coerência) foi analisada em três condições experimentais: bromazepam, placebo 1 e placebo 2. Os resultados sugerem que o bromazepam aumenta significativamente a coerência cortical inter-hemisférica.

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Caffeine is regarded as a central nervous system (CNS) stimulant. The goal of this study was to analyze electrophysiological, motor, cognitive and behavioral changes produced by caffeine ingestion after sleep deprivation. Ten subjects were evaluated after sleep deprivation, comparing the ingestion of either 400 mg of caffeine or placebo, in a double-blind randomized study. The variables analyzed were: quantitative EEG, the event-related potential (ERP-P300) and cognitive responses. The most significant quantitative EEG results, which were characterized by moment x treatment interactions, were seen in alpha and theta relative power variables. A significant decrease in relative alpha and theta was observed in the caffeine group after sleep deprivation. In relation to caffeine stimulant effects, there were no significant differences in the other parameters.

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UNLABELLED: The P300 component of the event-related potential (ERP) is a general measurement of "cognitive efficiency". It is an index of the ability of an individual's central nervous system (CNS) to process incoming information. OBJECTIVE: To compare the neuromodulatory effects of caffeine and bromazepam on the visual ERP (P300), in relation to a P300 normative database. METHOD: 15 right-handed individuals (7 male and 8 female), between 20 and 30 years of age, healthy, free of any cognitive impairment and not making use of psychoactive substances were studied. Participants were submitted to a visual discrimination task, which employed the "oddball" paradigm, after the administration of caffeine and bromazepam, in a randomized, double-blind design. RESULTS: Statistically significant differences were observed when the caffeine and bromazepam conditions were compared to the normative database. CONCLUSION: The present results suggest that caffeine and bromazepam have distinct modulatory effects on CNS functioning.

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Benzodiazepines have been used in the pharmacological treatment of anxiety for over four decades. However, very few studies have combined bromazepam and event-related potentials (ERP). The present study aimed at investigating the modulatory effects of this drug on brain dynamics. Specifically, the effects of bromazepam (3 mg) on the P300 component of the ERP were tested in a double-blind experiment. The sample, consisting of 15 healthy subjects (7 male and 8 female), was submitted to a visual discrimination task, which employed the "oddball" paradigm. Electrophysiological (P300) and behavioral measures (stroop, digit span, and reaction time) were analyzed across three experimental conditions: placebo 1, placebo 2, and bromazepam. Results suggest that the effects of bromazepam (3 mg) on cognitive processes are not apparent. In spite of what seems irrefutable in current literature, bromazepam did not produce evident effects on the behavioral and electrophysiological variables analyzed.

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Benzodiazepínicos têm sido utilizados no tratamento farmacológico da ansiedade há mais de quatro décadas. No entanto, poucos estudos têm combinado bromazepam e potencial evocado relacionado a evento (PRE). O presente estudo teve por objetivo investigar os efeitos modulatórios desta droga na dinâmica cerebral. Especificamente, os efeitos de 3mg de bromazepam no componente P300 do PRE foram analisados em um experimento duplo-cego. A amostra consistiu de 15 sujeitos sadios (7 homens e 8 mulheres), submetidos a uma tarefa de discriminação visual utilizando o paradigma "oddball". Medidas eletrofisiológicas (P300) e comportamentais (stroop, digit span, e tempo de reação) foram analisadas em três condições experimentais: placebo 1, placebo 2 e bromazepam. Os resultados sugerem que os efeitos de 3mg de bromazepam em processos cognitivos não são aparentes. Apesar do que parece irrefutável na literatura, o bromazepam não produziu efeitos evidentes nas variáveis comportamentais e eletrofisiológicas analisadas.

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O componente P300 do potencial evocado relacionado a evento é uma medida geral de "eficiência cognitiva" e um índice da qualidade do processamento e armazenamento de informações pelo sistema nervoso central (SNC). OBJETIVO: Comparar os efeitos neuromoduladores da cafeína e do bromazepam a partir do banco normativo do potencial evocado visual (P300). MÉTODO: 15 sujeitos destros (7 homens e 8 mulheres), entre 20 e 30 anos de idade, sadios, livres de qualquer déficit cognitivo e sem uso de substâncias psicotrópicas ou psicoativas foram estudados. Os sujeitos foram submetidos a uma tarefa de discriminação visual utilizando o paradigma "oddball", após a administração de uma cápsula de cafeína ou de bromazepam, em um desenho duplo-cego randomizado. RESULTADOS: Foram observadas diferenças estatisticamente significativas quando as condições cafeína e bromazepam foram comparadas com o banco normativo. CONCLUSÃO: Os resultados sugerem que a cafeína e o bromazepam têm efeitos moduladores específicos no SNC.

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O objetivo do presente estudo foi investigar alterações nos padrões eletroencefalográficos de sujeitos normais e destros durante o aprendizado motor de uma tarefa manual. Estudos recentes têm demonstrado que o córtex cerebral é suscetível a modificações em vários aspectos durante a aprendizagem e que tais alterações nos padrões eletrocorticais são resultado da aquisição de habilidades motoras e consolidação de memória. Para tal, a atividade elétrica cortical dos sujeitos foi analisada antes e depois da prática motora. Os dados foram captados pelo Braintech 3000 e analisados pelo programa Neurometrics. Para a análise estatística, variáveis comportamentais tais como tempo e erro foram observadas através de uma ANOVA one-way, blocos como efeito principal. Na variável neurofisiológica, potência absoluta, foi utilizado um teste t pareado a fim de detectar alterações entre os momentos pré e pós-aprendizagem, e diferentes eletrodos, CZ-C3/CZ-C4 em teta e alfa, e O1-P3/T3-F7 em beta. Os resultados principais demonstraram mudança na performance através das variáveis tempo e número de erros. Concomitantemente, foi verificado aumento de potência na banda alfa sobre áreas centrais (CZ-C3/CZ-C4) e diminuição em beta localizada na área temporoparietal esquerda (O1-P3/T3-F7). Alterações na banda teta, como demonstradas em outros experimentos, não ocorreram neste estudo. Tais resultados sugerem uma adaptação do córtex sensório-motor em que a alteração da atividade elétrica cortical é condizente com uma transição ao automatismo motor.

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BACKGROUND: The pathophysiology of eating disorders is still unknown, with many factors possibly involved. The existence of a central nervous system (CNS) dysfunction is being investigated with particular interest. One of the most employed strategies to reach this goal is the evaluation of cognitive functioning of patients with eating disorders with neuropsychological tests. OBJECTIVE: To evaluate the current knowledge about the neuropsychology of ED. METHODS: We performed a review of several data bases (including MedLINE, PsychoINFO, LILACS and Cochrane Data Bank), using terms related to main theme of interest. The review comprised articles published up to January, 2004. RESULTS: Anorexia Nervosa (AN) was the most studied ED from the neuropsychological point-of-view, with studies tending to elicit attentive, visuo-spatial, and visuo-constructive deficits among such patients. On the other side, patients with Bulimia Nervosa (BN) exhibited deficits in the selective aspects of attention and in executive functions. As yet, there is no study covering the neuropsychological aspects of binge-eating disorder. After successful treatment, individuals show improvement of some cognitive deficits, while other seem to persist. CONCLUSIONS: The ED are possibly associated with a certain degree of neuropsychological dysfunction, even though there is no consensus with regard to which function is particularly impaired. The fact that some cognitive dysfunction tend to disappear after treatment argues in favor of the hypothesis that these are functional deficits. Other deficits, however, tend to persist, suggesting that they may precede the development of eating disorders or even contribute to their development or to a worse prognosis. The study of the neuropsychological aspects of ED may help tailoring more selective therapeutic approaches to patients suffering from these disorders.

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O componente P300 do Potencial Evocado Relacionado a Evento é uma medida geral de "eficiência cognitiva" e um índice da qualidade do processamento e armazenamento de informações pelo sistema nervoso central. OBJETIVO: Desenvolvimento de um banco normativo do P300 visual. METODOLOGIA: 30 sujeitos destros (ambos os sexos), entre 20 e 30 anos de idade, sadios e livres de qualquer déficit cognitivo. Os sujeitos não estavam fazendo uso de substâncias psicotrópicas ou psicoativas e foram submetidos a uma tarefa de discriminação visual utilizando o paradigma "oddball". RESULTADOS: O padrão de distribuição cortical esperado foi observado para os valores de latência, mas não para os de amplitude. CONCLUSAO: Foi observada grande variabilidade dos valores de latência e amplitude no grupo analisado. O tempo de reação médio da amostra foi 391,56 ± 37,03 ms.

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O objetivo do presente estudo foi investigar alterações nos padrões eletroencefalográficos de sujeitos normais e destros durante o aprendizado de uma tarefa motora (datilografia). Estudos têm demonstrado que o córtex cerebral é susceptível a modificações durante a aprendizagem e que alterações nos padrões elétricos corticais ocorrem em função da aquisição de uma habilidade motora e da consolidação da memória. Assim, a atividade elétrica cortical dos sujeitos foi analisada antes e depois da prática motora. Os dados foram captados pelo "Braintech" 3000 e analisados pelo programa "Neurometrics". Para a análise estatística, variáveis comportamentais tais como tempo e erro, foram analisadas através do teste ANOVA "one-way" (diferenças entre blocos). Em seguida, foi utilizado um Teste-t pareado para os pares de eletrodos CZ-C3/CZ-C4, nas bandas de freqüência teta e alfa. Os resultados principais demonstraram mudança na performance através das variáveis comportamentais "tempo" e "número de erros". Concomitantemente, não foram observadas alterações na variável neurofisiológica "Potência Absoluta" na banda teta. Em contrapartida, houve um aumento significativo na banda alfa em áreas centrais (CZ-C3/CZ-C4). Tais resultados sugerem uma adaptação do córtex sensório-motor em função do treinamento de datilografia.

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UNLABELLED: The P300 component of the Event-Related Potential (ERP) is a general measurement of "cognitive efficiency". It is an index of the ability of an individual's Central Nervous System (CNS) to process incoming information. OBJECTIVE: To develop a normative database for the visual P300. METHODOLOGY: 30 right-handed individuals (same number of each sex), between 20 and 30 years of age, healthy, free of any cognitive impairment and not making use of psychoactive substances. Participants were submitted to a visual discrimination task, which employed the "oddball" paradigm. RESULTS: The expected scalp distribution trend was seen for latency but not for amplitude values. CONCLUSION: A high variability of latency and amplitude values was observed across the age span. Mean reaction time for the entire sample of the study was 391.56 +/- 37.03 ms.

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The present study aimed to investigate alterations in EEG patterns in normal, right-handed individuals, during the process of learning a specific motor skill (typewriting). Recent studies have shown that the cerebral cortex is susceptible to several changes during a learning process and that alterations in the brain's electrical patterns take place as a result of the acquisition of a motor skill and memory consolidation. In this context, subjects' brain electrical activity was analyzed before and after the motor task. EEG data were collected by a Braintech 3000 and analyzed by Neurometrics. For the statistical analysis, the behavioral variables "time" and "number of errors" were assessed by a one-way ANOVA. For the neurophysiological variable "Absolute Power", a paired t-Test was performed for each pair of electrodes CZ-C3/CZ-C4, in the theta and alpha frequency bands. The main results demonstrated a change in performance, through both behavioral variables ("time" and "number of errors"). At the same time, no changes were observed for the neurophysiological variable ("Absolute Power") in the theta band. On the other hand, a significant increase was observed in the alpha band in central areas (CZ-C3/CZ-C4). These results suggest an adaptation of the sensory-motor cortex, as a consequence of the typewriting training.

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