TRANSCRANIAL DIRECT CURRENT STIMULATION AND MANUAL ASYMMETRIES: THE EFFECT OF THE STIMULATION ON THE MANUAL DEXTERITY

ABSTRACT The aim of this study was to evaluate the effect of transcranial direct-current stimulation (tDCS) on the primary motor cortex (M1) in the manual performance asymmetries in a manual dexterity tasks. The sample consisted of 28 volunteers, right-handed, men and without neurological impairment. The task (Grooved Pegboard) consisted of inserting 25 pins in 25 receptacles, as soon as possible. The task was executed in the pretest with both hands to define the level of manual asymmetry. tDCS or Sham were applied a week after the pretest, then the subjects were evaluated in the post-test. The results revealed that the effects of tDCS in M1 did not reduce asymmetries in a manual dexterity task. However, only the tDCS group improved the performance from pretest to the posttest (p摘要 本研究旨在评估经颅直流电刺激（transcranial direct-current stimulation, tDCS）对初级运动皮层（primary motor cortex, M1）在手部灵活性任务中运动表现不对称性的影响。本研究共纳入28名男性右利手志愿者，均无神经功能障碍。实验任务为槽钉板（Grooved Pegboard）：要求受试者尽快将25枚插钉插入25个插孔中。预测试阶段要求受试者使用双手完成该任务，以确定其手部运动不对称性水平。预测试一周后，对受试者施加经颅直流电刺激或假刺激，随后开展后测试评估。结果显示，针对初级运动皮层的经颅直流电刺激并未降低手部灵活性任务中的运动表现不对称性。但仅经颅直流电刺激组的任务表现从预测试至后测试得到提升（p