Estimulação cerebral na promoção da saúde e melhoria do desempenho físico

O avanço tecnológico das últimas décadas tem proporcionado o uso eficaz de técnicas não-invasivas na neuromodulação cerebral. Atualmente, as principais técnicas de neuromodulação são a estimulação magnética transcraniana (EMT) e a estimulação transcraniana por corrente contínua (ETCC). Por meio de revisão da literatura, o presente estudo aborda: a) história da estimulação cerebral; b) mecanismos de ação estudados através da neurofisiologia motora, farmacologia, neuroimagem e animais experimentais; c) perspectivas de aplicações da estimulação cerebral para promoção da saúde e melhoria do desempenho físico, incluindo o controle autonômico cardíaco e hipotensão pós-exercício, o controle de apetite e a modulação da fadiga e desempenho físico; e d) aspectos de segurança referentes ao uso da ETCC. Dessa forma, a ETCC parece ser uma técnica efetiva e segura para modular a função cerebral e podemos vislumbrar algumas perspectivas de aplicação no âmbito da ingestão alimentar, saúde cardiovascular e desempenho físico.The technological advances of the last decades have provided the effective use of noninvasive techniques in neuromodulation with concomitant health benefits. Currently, the main neuromodulation techniques are transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). Through literature review, this study addresses the a) history of brain stimulation and the b) mechanisms of action studied by motor neurophysiology, pharmacology, neuroimaging, and experimental animals. Moreover, it is presented the c) perspectives for applications of brain stimulation for promoting health and improving physical performance, including cardiac autonomic control and post-exercise hypotension, control and modulation of appetite, fatigue and physical performance. Finally, we describe d) the security aspects related to the use of tDCS. Thus, tDCS seems to be an effective and safe technique to modulate brain function and suggests some application associated to food intake, cardiovascular health and physical performance

Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

An increased understanding of the relationship between structural connections and functional and behavioral outcomes is an essential but under-explored topic in neuroscience. During transcranial direct current stimulation (tDCS)-induced analgesia, neuromodulation occurs through a top-down process that depends on inter-regional connections. To investigate whether variation in anatomical connectivity explains functional and behavorial outcomes during neuromodulation, we first combined tDCS and a tonic pain model with concurrent arterial spin labelling that measures cerebral perfusion related to ongoing neural activity. Left dorsolateral prefrontal cortex (L-DLPFC) tDCS induced an analgesic effect, which was explained by reduced perfusion to posterior insula and thalamus. Second, we used diffusion imaging to assess white matter structural integrity between L-DLPFC and thalamus, two key components of the neuromodulatory network. Fractional anisotropy of this tract correlated positively with functional and behavioral modulations. This suggests structural dependence by the neuromodulatory process to induce analgesia with potential relevance for patient stratification