Boggio Paulo S, Castro Letícia O, Savagim Edna A, Braite Renata, Cruz Viviane C, Rocha Renata R, Rigonatti Sergio P, Silva Maria T A, Fregni Felipe
Department of Experimental Psychology, University of Sao Paulo, Brazil.
Neurosci Lett. 2006 Aug 14;404(1-2):232-6. doi: 10.1016/j.neulet.2006.05.051. Epub 2006 Jun 30.
Transcranial direct current stimulation (tDCS) is a non-invasive powerful method to modulate brain activity. It can enhance motor learning and working memory in healthy subjects. To investigate the effects of anodal tDCS (1 mA, 20 min) of the dominant and non-dominant primary motor cortex (M1) on hand motor performance in healthy right-handed volunteers, healthy subjects underwent one session of both sham and active anodal stimulation of the non-dominant or dominant primary motor cortex. A blinded rater assessed motor function using the Jebsen Taylor Hand Function Test. For the non-dominant hand, active tDCS was able to improve motor function significantly-there was a significant interaction between time and condition of stimulation (p = 0.003). Post hoc tests showed a significant enhancement of JTT performance after 1 mA anodal tDCS of M1 (mean improvement of 9.41%, p = 0.0004), but not after sham tDCS (mean improvement of 1.3%, p = 0.84). For the dominant hand, however, neither active nor sham tDCS resulted in a significant change in motor performance. Our findings show that anodal tDCS of the non-dominant primary motor cortex results in motor function enhancement and thus confirm and extend the notion that tDCS can change behavior. We speculate that the under-use of the non-dominant hand with its associated consequences in cortical plasticity might be one of the reasons to explain motor performance enhancement in the non-dominant hand only.
经颅直流电刺激（tDCS）是一种调节大脑活动的非侵入性有力方法。它可以增强健康受试者的运动学习和工作记忆。为了研究对健康右利手志愿者优势和非优势初级运动皮层（M1）进行阳极tDCS（1毫安，20分钟）对手部运动表现的影响，健康受试者接受了非优势或优势初级运动皮层的假刺激和阳极主动刺激各一次。一名不知情的评估者使用杰布森·泰勒手部功能测试评估运动功能。对于非优势手，主动tDCS能够显著改善运动功能——刺激时间和条件之间存在显著交互作用（p = 0.003）。事后检验显示，M1接受1毫安阳极tDCS后，JTT表现有显著提高（平均提高9.41%，p = 0.0004），但假刺激后没有（平均提高1.3%，p = 0.84）。然而，对于优势手，主动和假tDCS均未导致运动表现出现显著变化。我们的研究结果表明，非优势初级运动皮层的阳极tDCS可导致运动功能增强，从而证实并扩展了tDCS可以改变行为的观点。我们推测，非优势手使用不足及其在皮质可塑性方面的相关后果可能是仅能解释非优势手运动表现增强的原因之一。
