Lee Minji, Kim Yun-Hee, Im Chang-Hwan, Kim Jung-Hoon, Park Chang-hyun, Chang Won Hyuk, Lee Ahee
Department of Health Sciences and Technology, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea.
Department of Health Sciences and Technology, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea; Department of Physical and Rehabilitation Medicine, Center for Prevention & Rehabilitation, Heart Vascular and Stroke, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea.
Neurosci Lett. 2015 Jan 1;584:347-50. doi: 10.1016/j.neulet.2014.10.052. Epub 2014 Nov 3.
Transcranial direct current stimulation (tDCS) non-invasively modulates brain function by inducing neuronal excitability. The conventional hot spot for inducing the highest current density in the hand motor area may not be the optimal site for effective stimulation. In this study, we investigated the influence of the center position of the anodal electrode on changes in motor cortical excitability. We considered three tDCS conditions in 16 healthy subjects: (i) real stimulation with the anodal electrode located at the conventional hand motor hot spot determined by motor evoked potentials (MEPs); (ii) real stimulation with the anodal electrode located at the point with the highest current density in the hand motor area as determined by electric current simulation; and (iii) sham stimulation. Motor cortical excitability as measured by MEP amplitude increased after both real stimulation conditions, but not after sham stimulation. Stimulation using the simulation-derived anodal electrode position, which was found to be posterior to the MEP hot spot for all subjects, induced higher motor cortical excitability. Individual positioning of the anodal electrode, based on the consideration of anatomical differences between subjects, appears to be important for maximizing the effects of tDCS.
经颅直流电刺激（tDCS）通过诱导神经元兴奋性来无创调节脑功能。在手部运动区诱导最高电流密度的传统热点可能并非有效刺激的最佳部位。在本研究中，我们调查了阳极电极中心位置对运动皮质兴奋性变化的影响。我们对16名健康受试者考虑了三种tDCS条件：（i）阳极电极位于由运动诱发电位（MEP）确定的传统手部运动热点处进行真实刺激；（ii）阳极电极位于由电流模拟确定的手部运动区电流密度最高的点进行真实刺激；（iii）假刺激。在两种真实刺激条件后，通过MEP振幅测量的运动皮质兴奋性均增加，但在假刺激后未增加。使用模拟得出的阳极电极位置进行刺激，发现对所有受试者而言该位置在MEP热点后方，可诱导更高的运动皮质兴奋性。基于考虑受试者之间的解剖差异对阳极电极进行个体化定位，对于最大化tDCS的效果似乎很重要。
