Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China.
Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Hong Kong SAR, China.
J Neuroeng Rehabil. 2024 Sep 20;21(1):169. doi: 10.1186/s12984-024-01468-w.
Delivering HD-tDCS on individual motor hotspot with optimal electric fields could overcome challenges of stroke heterogeneity, potentially facilitating neural activation and improving motor function for stroke survivors. However, the intervention effect of this personalized HD-tDCS has not been explored on post-stroke motor recovery. In this study, we aim to evaluate whether targeting individual motor hotspot with HD-tDCS followed by EMG-driven robotic hand training could further facilitate the upper extremity motor function for chronic stroke survivors.
In this pilot randomized controlled trial, eighteen chronic stroke survivors were randomly allocated into two groups. The HDtDCS-group (n = 8) received personalized HD-tDCS using task-based fMRI to guide the stimulation on individual motor hotspot. The Sham-group (n = 10) received only sham stimulation. Both groups underwent 20 sessions of training, each session began with 20 min of HD-tDCS and was then followed by 60 min of robotic hand training. Clinical scales (Fugl-meyer Upper Extremity scale, FMAUE; Modified Ashworth Scale, MAS), and neuroimaging modalities (fMRI and EEG-EMG) were conducted before, after intervention, and at 6-month follow-up. Two-way repeated measures analysis of variance was used to compare the training effect between HDtDCS- and Sham-group.
HDtDCS-group demonstrated significantly better motor improvement than the Sham-group in terms of greater changes of FMAUE scores (F = 6.5, P = 0.004) and MASf (F = 3.6, P = 0.038) immediately and 6 months after the 20-session intervention. The task-based fMRI activation significantly shifted to the ipsilesional motor area in the HDtDCS-group, and this activation pattern increasingly concentrated on the motor hotspot being stimulated 6 months after training within the HDtDCS-group, whereas the increased activation is not sustainable in the Sham-group. The neuroimaging results indicate that neural plastic changes of the HDtDCS-group were guided specifically and sustained as an add-on effect of the stimulation.
Stimulating the individual motor hotspot before robotic hand training could further enhance brain activation in motor-related regions that promote better motor recovery for chronic stroke.
This study was retrospectively registered in ClinicalTrials.gov (ID NCT05638464).
在个体运动热点部位施加高密度经颅直流电刺激（HD-tDCS），以优化电场，可能克服卒中异质性带来的挑战，促进卒中幸存者的神经激活和运动功能恢复。然而，这种个体化 HD-tDCS 的干预效果尚未在卒中后运动恢复方面得到探索。本研究旨在评估针对个体运动热点部位的 HD-tDCS 联合肌电驱动机器人手训练是否能进一步促进慢性卒中幸存者的上肢运动功能。
这是一项前瞻性随机对照试验，18 名慢性卒中幸存者被随机分为两组。HDtDCS 组（n=8）接受基于任务的 fMRI 引导的个体化 HD-tDCS，以刺激个体运动热点部位。假刺激组（n=10）仅接受假刺激。两组均接受 20 次训练，每次训练包括 20 分钟的 HD-tDCS 和 60 分钟的机器人手训练。在干预前、干预后和 6 个月随访时，采用临床量表（Fugl-Meyer 上肢量表，FMAUE；改良 Ashworth 量表，MAS）和神经影像学方法（fMRI 和 EEG-EMG）进行评估。采用双向重复测量方差分析比较 HDtDCS 组和假刺激组的训练效果。
与假刺激组相比，HDtDCS 组在干预后即刻和 6 个月时 FMAUE 评分（F=6.5，P=0.004）和 MASf（F=3.6，P=0.038）的改善更为显著。HDtDCS 组基于任务的 fMRI 激活明显向对侧运动区转移，且这种激活模式在训练 6 个月后逐渐集中在被刺激的运动热点部位，而假刺激组的激活则不可持续。神经影像学结果表明，HDtDCS 组的神经可塑性变化是特定的、可持续的，是刺激的附加效应。
在机器人手训练前刺激个体运动热点部位可以进一步增强与运动相关区域的脑激活，从而促进慢性卒中患者更好的运动恢复。
本研究在 ClinicalTrials.gov 进行了回顾性注册（ID NCT05638464）。
