The Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Neuroimage. 2011 Aug 1;57(3):885-91. doi: 10.1016/j.neuroimage.2011.05.026. Epub 2011 May 18.
Transcranial direct current stimulation (tDCS) has recently emerged as a promising approach to enhance neurorehabilitative outcomes. However, little is known about how the local electrical field generated by tDCS relates to underlying neuroplastic changes and behavior. To address this question, we present a case study analysis of an individual with hemianopia due to stroke and who benefited from a combined visual rehabilitation training and tDCS treatment program. Activation associated with a visual motion perception task (obtained by functional magnetic resonance imaging; fMRI) was used to characterize local changes in brain activity at baseline and after training. Individualized, high-resolution electrical field modeling reproducing precise cerebral and lesioned tissue geometry, predicted distortions of current flow in peri-lesional areas and diffuse clusters of peak electric fields. Using changes in fMRI signal as an index of cortical recovery, correlations to the electrical field map were determined. Significant correlations between the electrical field and change in fMRI signal were region specific including cortical areas under the anode electrode and peri-lesional visual areas. These patterns were consistent with effective tDCS facilitated rehabilitation. We describe the methodology used to analyze tDCS mechanisms through combined fMRI and computational modeling with the ultimate goal of developing a rationale for individualized therapy.
经颅直流电刺激（tDCS）最近作为一种增强神经康复效果的有前途的方法出现。然而，对于 tDCS 产生的局部电场如何与潜在的神经可塑性变化和行为相关知之甚少。为了解决这个问题，我们对一名因中风而导致偏盲的个体进行了案例研究分析，该个体受益于联合视觉康复训练和 tDCS 治疗方案。使用与视觉运动感知任务相关的激活（通过功能磁共振成像；fMRI）来描述基线和训练后的大脑活动的局部变化。复制精确的大脑和损伤组织几何形状的个体化、高分辨率电场建模，预测了损伤区域周围电流流动的扭曲和峰值电场的弥散集群。使用 fMRI 信号的变化作为皮质恢复的指标，确定与电场图的相关性。电场与 fMRI 信号变化之间的相关性具有特定区域的特征，包括阳极电极下的皮质区域和损伤周围的视觉区域。这些模式与有效的 tDCS 促进康复一致。我们描述了通过结合 fMRI 和计算建模来分析 tDCS 机制的方法，最终目标是为个体化治疗制定合理的方案。
