Schestatsky Pedro, Morales-Quezada Leon, Fregni Felipe
Programa de Pós-Graduação em Ciências Médica, Universidade Federal do Rio Grande do Sul.
J Vis Exp. 2013 Jun 17(76):50426. doi: 10.3791/50426.
Transcranial direct current stimulation (tDCS) is a technique that delivers weak electric currents through the scalp. This constant electric current induces shifts in neuronal membrane excitability, resulting in secondary changes in cortical activity. Although tDCS has most of its neuromodulatory effects on the underlying cortex, tDCS effects can also be observed in distant neural networks. Therefore, concomitant EEG monitoring of the effects of tDCS can provide valuable information on the mechanisms of tDCS. In addition, EEG findings can be an important surrogate marker for the effects of tDCS and thus can be used to optimize its parameters. This combined EEG-tDCS system can also be used for preventive treatment of neurological conditions characterized by abnormal peaks of cortical excitability, such as seizures. Such a system would be the basis of a non-invasive closed-loop device. In this article, we present a novel device that is capable of utilizing tDCS and EEG simultaneously. For that, we describe in a step-by-step fashion the main procedures of the application of this device using schematic figures, tables and video demonstrations. Additionally, we provide a literature review on clinical uses of tDCS and its cortical effects measured by EEG techniques.
经颅直流电刺激（tDCS）是一种通过头皮施加弱电流的技术。这种恒定电流会引起神经元膜兴奋性的变化，从而导致皮层活动的继发性改变。尽管tDCS的大多数神经调节作用发生在其下方的皮层，但在远处的神经网络中也能观察到tDCS的效应。因此，同步进行脑电图（EEG）监测tDCS的效应，可以为tDCS的作用机制提供有价值的信息。此外，EEG结果可以作为tDCS效应的重要替代指标，从而用于优化其参数。这种EEG-tDCS联合系统还可用于预防性治疗以皮层兴奋性异常峰值为特征的神经系统疾病，如癫痫发作。这样的系统将成为无创闭环设备的基础。在本文中，我们介绍了一种能够同时利用tDCS和EEG的新型设备。为此，我们通过示意图、表格和视频演示，逐步描述了该设备应用的主要步骤。此外，我们还对tDCS的临床应用及其通过EEG技术测量的皮层效应进行了文献综述。
