Target optimization in transcranial direct current stimulation.
Target optimization in transcranial direct current stimulation.
复制标题
经颅直流电流刺激中的目标优化。
DOI：
10.3389/fpsyt.2012.00090
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发表时间：
2012
影响因子：
4.7
通讯作者：
Gordon B
中科院分区：
文献类型：
--
作者：
Sadleir RJ;Vannorsdall TD;Schretlen DJ;Gordon B
经颅直流电刺激（tDCS）是一种新兴的神经调节疗法，已通过实验确定其影响范围广泛的行为和疾病，从运动、认知和记忆过程到抑郁和疼痛综合征。tDCS的作用可能是抑制性或兴奋性的，这取决于电极的相对极性及其与不同大脑结构的接近程度。这种区别被认为与电流与不同神经复合体的激活阈值的相互作用有关。tDCS电流通常通过单对大电极施加，其中一个（有源电极）位于与目标过程相关的大脑结构附近。为了有效地将电流导向与这些效应相关的区域，我们设计了一种方法，通过参考应用于头部高分辨率有限元模型的19电极蒙太奇，将电流导向选定区域。我们使用非线性优化程序来最大化左侧额下回（IFG）内的平均电流密度，同时限制伏隔内的总电流和中位数电流密度。我们发现，可以找到一个分布式的电流模式，确实会以这种方式将电流导向IFG，并将其与其他候选2电极配置进行比较。此外，我们发现四个前后电极的组合可以将电流密度引导到小脑。我们的结论是，使用多个电极的类似方法可能是一种有用的手段，引导电流朝向或远离特定的大脑区域，并减少tDCS的副作用。
Transcranial direct current stimulation (tDCS) is an emerging neuromodulation therapy that has been experimentally determined to affect a wide range of behaviors and diseases ranging from motor, cognitive, and memory processes to depression and pain syndromes. The effects of tDCS may be inhibitory or excitatory, depending on the relative polarities of electrodes and their proximity to different brain structures. This distinction is believed to relate to the interaction of current flow with activation thresholds of different neural complexes. tDCS currents are typically applied via a single pair of large electrodes, with one (the active electrode) sited close to brain structures associated with targeted processes. To efficiently direct current toward the areas presumed related to these effects, we devised a method of steering current toward a selected area by reference to a 19-electrode montage applied to a high-resolution finite element model of the head. We used a non-linear optimization procedure to maximize mean current densities inside the left inferior frontal gyrus (IFG), while simultaneously restricting overall current, and median current densities within the accumbens. We found that a distributed current pattern could be found that would indeed direct current toward the IFG in this way, and compared it to other candidate 2-electrode configurations. Further, we found a combination of four anterior-posterior electrodes could direct current densities to the accumbens. We conclude that a similar method using multiple electrodes may be a useful means of directing current toward or away from specific brain regions and also of reducing tDCS side effects.