BACKGROUND Recording electroencephalography (EEG) from the targeted cortex immediately before and after focal transcranial electrical stimulation (TES) remains a challenge. METHODS We introduce a hybrid stimulation-recording approach where a single EEG electrode is inserted into the inner electrode of a double-ring montage for focal TES. The new combined electrode was placed at the C3 position of the EEG 10-20 system. Neuronal activity was recorded in two volunteers before and after 20 Hz alternating-current TES at peak-to-peak intensities of 1 and 2 mA. TES-induced electric field distributions were simulated with SIMNIBS software. RESULTS Using the hybrid stimulation-recording set-up, EEG activity was successfully recorded directly before and after TES. Simulations revealed comparable electrical fields in the stimulated cortex for the pseudomonopolar montage with and without embedded EEG electrode. CONCLUSION The hybrid TES-EEG approach can be used to probe after-effects of focal TES on neuronal activity in the targeted cortex.

中文翻译：

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在局灶性经颅电刺激后探测目标皮层的脑电图活动

背景技术在局灶性经颅电刺激（TES）之前和之后立即记录来自目标皮层的脑电图（EEG）仍然是一个挑战。方法我们引入了一种混合刺激记录方法，其中将单个 EEG 电极插入双环蒙太奇的内部电极中，用于焦点 TES。新的组合电极放置在 EEG 10-20 系统的 C3 位置。在 20 Hz 交流电 TES 之前和之后以 1 mA 和 2 mA 的峰峰值强度记录了两名志愿者的神经元活动。用 SIMNIBS 软件模拟 TES 诱导的电场分布。结果 使用混合刺激记录设置，在 TES 前后直接成功记录了 EEG 活动。模拟结果显示，带有和不带有嵌入式 EEG 电极的假单极蒙太奇刺激皮层中的电场具有可比性。结论 混合 TES-EEG 方法可用于探测局灶性 TES 对目标皮层神经元活动的后效。