當病患發生中風時，會造成運動功能障礙導致無法自主活動，部分原因係由於中風後導致左右半腦的神經網路不平衡所造成。近年有研究指出，利用經顱直流電刺激(transcranial direct current stimulation, tDCS)可在短期內改變大腦皮質的興奮度，使兩側大腦回復平衡狀態。本實驗室過去所研究之腦機介面(Brain-Computer-Interface, BCI)控制復健矯形手，可進行中風病患之動作想像訓練，並藉由視覺與本體感覺的回饋，達到視動整合的效果，促進活動相依大腦重塑(activity-dependent brain plasticity)，並藉此增進其運動學習能力。
本研究以過去對於腦波分析及復健機器人之研究為基礎，結合經顱直流電刺激與腦機介面控制復健矯形手，期望藉由此兩種不同的大腦神經活化機制，能提升中風病患的復健成效。腦機介面識別系統部分使用共同空間型樣法(common spatial pattern, CSP)，找出受測者對於想像左/右手動作時之差異較顯著的腦波特徵訊號，以提高事件相關腦波的辨識率。本研究共徵召6位常人與3位中風病人，實驗設計上採取隨機、雙盲、交叉試驗。
研究結果顯示，陽極電刺激能有效提升中風病患於腦機介面的控制成功率，但在反應時間上沒有明顯改善，而對於常人，似乎均沒有顯著效益，此外，藉由複雜網路分析大腦聯結變化與功能性磁振造影結果發現，受測者接受陽極電刺激介入後，神經結點聯結數增加，聯結訊號強度增強，聯結聚集程度較密集，由此推測陽極電刺激可能使大腦重塑，而由臨床量表的改善可以看出陽極電刺激結合腦機介面控制複健矯形手能強化中風病患的復健效果。

The aims of this study were to investigate the effects of combining tDCS with EEG-based BCI for orthotic hands control in chronic stroke patients and to compare the therapeutic effects of anodal-tDCS and sham-tDCS. 6 healthy individuals and 3 stroke patients participated in this randomized, double-blinded, crossover study. The testing protocol was approved by Internal Review Board of National Cheng Kung University Hospital. Each subject received two interventions, namely anodal-tDCS (a-tDCS) and sham-tDCS (s-tDCS) followed by BCI training. Due to technical difficulty, BCI control of hand orthosis could only be conducted after tDCS session. In the BCI training, imaginary thumb movement was utilized to trigger the motor of the orthosis and to extend fingers of the subject. The results showed significant improvements in accuracy of orthosis control via the BCI with a-tDCS compared with s-tDCS of stroke patients. But there were no evident differences between the two interventions in trigger time. The brain connectivity analysis revealed that subjects with a-tDCS intervention, had higher global degree, global coupling strength and clustering coefficient than s-tDCS intervention. The results concluded that anodal stimulation might improve implicit motor learning and facilitate the reconstruction of cortical circuits in stroke patients.

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