Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Aichi 466-8555, Japan.
Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Aichi 466-8555, Japan; Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan; Center for Frontier Medical Engineering, Chiba University, Chiba 263-8522, Japan.
Clin Neurophysiol. 2023 Jun;150:69-78. doi: 10.1016/j.clinph.2023.03.009. Epub 2023 Mar 27.
Transcranial direct current stimulation (tDCS) injects a weak electric current into the brain via electrodes attached to the scalp to modulate cortical excitability. tDCS is used to rebalance brain activity between affected and unaffected hemispheres in rehabilitation. However, a systematic quantitative evaluation of tDCS montage is not reported for the lower limbs. In this study, we computationally investigated the generated electric field intensity, polarity, and co-stimulation of cortical areas for lower limb targeting using high-resolution head models.
Volume conductor models have thus been employed to estimate the electric field in the brain. A total of 18 head models of healthy subjects were used to calculate the group-level electric fields generated from four montages of tDCS for modulation of lower limbs.
C1-C2 montage delivered higher electric field intensities while reaching deeper regions of the lower-limb motor area. It produced a uniform polarization on the same hemisphere target with comparable intensities between hemispheres but with higher variability.
Proper montage selection allows reaching deeper regions of the lower-limb motor area with uniform polarization.
First systematic computational study providing support to tDCS experimental studies using montages for the lower limb while considering polarity factor for balancing brain activity.
经颅直流电刺激（tDCS）通过贴在头皮上的电极将弱电流注入大脑，从而调节皮质兴奋性。tDCS 用于在康复过程中重新平衡受影响和未受影响半球之间的大脑活动。然而，对于下肢，并没有系统地对 tDCS 刺激模式进行定量评估。在这项研究中，我们使用高分辨率的头部模型，从计算的角度研究了针对下肢目标的皮质区域的电场强度、极性和共同刺激。
因此，采用容积导体模型来估计大脑中的电场。使用总共 18 个健康受试者的头部模型，计算了从用于调节下肢的四种 tDCS 刺激模式中产生的组级电场。
C1-C2 刺激模式在到达下肢运动区域的更深层时提供了更高的电场强度。它在同侧目标上产生了均匀的极化，并且两侧之间的强度相当，但变异性更高。
适当的刺激模式选择可以使下肢运动区域的更深层达到均匀的极化。
这是第一项针对下肢使用刺激模式的系统计算研究，同时考虑了平衡大脑活动的极性因素，为 tDCS 实验研究提供了支持。
