Emotion regulation can be achieved through a number of processes. Previous studies have investigated this issue by encouraging individuals to voluntarily change how they think about a situation in order to decrease its emotional impact. However, little is known about automatic regulation processes. The goal of the present study was to investigate whether an "implicit reappraisal strategy" would modulate the Late Positive Potential (LPP) associated to affective picture viewing. Unpleasant pictures, presented as distractors, were shown in two contexts in which a prior description presented them as taken from either movie scenes (fictitious) or real scenes. Results showed that the interference produced by unpleasant pictures under the real context, indexed by reaction time and LPP amplitude, was attenuated under the fictitious context. These results provide evidence for implicit down-regulation of the stimulus relevance during an inattention condition.

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-Exercise has been widely related to changes in cortical activation and enhanced brain functioning. Quantitative electroencephalography (qEEG) is frequently used to investigate normal and pathological conditions in the brain cortex. Therefore, the aim of the present study was to observe absolute power alterations in beta and alpha frequency bands after a maximal effort exercise. Ten healthy young volunteers were submitted to an eight-minute resting EEG (eyes closed) followed by a maximal exercise test using a mechanical cycle ergometer. Immediately after the exercise, another identical eight-minute EEG was recorded. Log transformation and paired student's t-test compared the pre and post exercise values (p<0.05). Results indicated a significant absolute power increase in beta after exercise at frontal (Fp1, F3 and F4) and central (C4) areas, which might be related to increased cortical activation. KEY WORDS: EEG, exercise, cortical activationAlterações eletrencefalográficas nas bandas de frequência alfa e beta após exercício de esforço máximo RESUMO -A atividade física vem sendo relacionada com ativação cortical e melhor funcionamento do cére-bro. A eletrencefalografia quantitativa (EEGq) é freqüentemente usada para investigar condições normais e patológicas do córtex cerebral. Sendo assim, o objetivo do presente estudo foi observar alterações na potência absoluta nas bandas de freqüência alfa e beta após um exercício de esforço máximo. Dez voluntá-rios jovens e saudáveis foram submetidos a oito minutos de EEG antes e após um teste de esforço máximo em cicloergômetro. As transformações para o log e o teste t de Student foram utilizados para comparar as respostas eletrencefalográficas entre os momentos pré e pós exercício. Foi observado aumento significativo na potência absoluta de beta após o exercício nos eletrodos frontais (Fp1, F3, F4) e centrais (C4). Este resultado pode estar associado a alterações fisiológicas e ao aumento da ativação cortical.PALAvRAS-ChAvE: EEG, exercício, ativação cortical.

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Some patients are no longer able to communicate effectively or even interact with the outside world in ways that most of us take for granted. In the most severe cases, tetraplegic or post-stroke patients are literally 'locked in' their bodies, unable to exert any motor control after, for example, a spinal cord injury or a brainstem stroke, requiring alternative methods of communication and control. But we suggest that, in the near future, their brains may offer them a way out. Non-invasive electroencephalogram (EEG)-based brain-computer interfaces (BCI) can be characterized by the technique used to measure brain activity and by the way that different brain signals are translated into commands that control an effector (e.g., SYNOPSIScontrolling a computer cursor for word processing and accessing the internet). This review focuses on the basic concepts of EEGbased BCI, the main advances in communication, motor control restoration and the downregulation of cortical activity, and the mirror neuron system (MNS) in the context of BCI. The latter appears to be relevant for clinical applications in the coming years, particularly for severely limited patients. Hypothetically, MNS could provide a robust way to map neural activity to behavior, representing the high-level information about goals and intentions of these patients. Non-invasive EEG-based BCIs allow brain-derived communication in patients with amyotrophic lateral sclerosis and motor control restoration in patients after spinal cord injury and stroke. Epilepsy and attention deficit and hyperactive disorder patients were able to downregulate their cortical activity. Given the rapid progression of EEG-based BCI research over the last few years and the swift ascent of computer processing speeds and signal analysis techniques, we suggest that emerging ideas (e.g., MNS in the context of BCI) related to clinical neurorehabilitation of severely limited patients will generate viable clinical applications in the near future. VOLUME 21, NO. 6,2010 451 Brought to you by | provisional account Unauthenticated Download Date | 6/7/15 7:42 AM 452 S. MACHADO ET AL. KEY WORDSAmyotrophic Lateral Sclerosis, attention deficit and hyperactive disorder, EEG-based braincomputer interface, epilepsy, mirror neurons system, sensorimotor integration, spinal cord, stroke