We recently conducted a study examining whether transcranial electrical stimulation (TES) motor threshold (MT), reversecalculation transcranial direct current stimulation (tDCS) electric field modeling, or both could potentially be used as methods of individualizing tDCS doses(1). We found that TES MT significantly correlates with a reverse-calculated tDCS dosage in the motor cortex andwere intrigued by the possibility of using TESMTas anMRIfree method of individually dosing tDCS(1). A limitation of this previous workwas that we did not test the utility of TESMT to estimate reverse-calculation tDCS doses outside of the motor cortex. Here we extend this research by assessing whether TES MT correlates with reverse-calculation electric field models of prefrontal stimulation in a common F3-F4 electrode montage that has been used in depression [2], drug craving [3], working memory [4], and many other conditions. In this study we used the same dataset as in Ref. [1], inwhich we acquired transcranial magnetic stimulation (TMS) MT, TES MT, and anatomical T1w MRI scans for 29 healthy adults (15 women, mean age 1⁄4 26.9, SD 1⁄4 9.1). We previously described the two-visit study protocol in depth in Ref. [1] but briefly describe it here. In Visit 1, we placed a plastic cap on each participant’s head and used a closedloop TMS-motor evoked potential (MEP) acquisition setup using single pulses of TMS (Magstim BiStim machine with 70mm figure-of-eight Remote Coil; Whitland, Wales, UK) over the left motor hotspot and electromyography (EMG) electrodes over the contralateral right hand [5]. We defined a positive MEP as having a peak-to-peak amplitude of 0.05mV, and used PEST software (https://www.clinicalresearcher.org/software.htm) to determine the next stimulation intensity for MT acquisition [6]. After determining the TMS MT, we cut through the plastic cap to place a 35 20mm electrode (Natus Neurology Inc., Pleasanton, CA, USA)

中文翻译：

---

经颅电刺激运动阈值能否估计前额叶皮层的个体化 tDCS 剂量？来自逆向计算电场建模的证据

我们最近进行了一项研究，检查经颅电刺激 (TES) 运动阈值 (MT)、逆向计算经颅直流电刺激 (tDCS) 电场建模，或两者都可能用作个体化 tDCS 剂量的方法 (1)。我们发现 TES MT 与运动皮层中反向计算的 tDCS 剂量显着相关，并且对使用 TESMT 作为单独给药 tDCS(1) 的 MRIfree 方法的可能性很感兴趣。之前这项工作的一个限制是我们没有测试 TESMT 的效用来估计运动皮层外的反向计算 tDCS 剂量。在这里，我们通过评估 TES MT 是否与用于抑郁症的常见 F3-F4 电极蒙太奇中前额叶刺激的反向计算电场模型相关来扩展这项研究 [2]，药物渴望 [3]、工作记忆 [4] 和许多其他条件。在这项研究中，我们使用了与参考文献相同的数据集。[1]，其中我们获得了 29 名健康成人（15 名女性，平均年龄 1⁄4 26.9，SD 1⁄4 9.1）的经颅磁刺激 (TMS) MT、TES MT 和解剖 T1w MRI 扫描。我们之前在参考文献中深入描述了两次访问研究方案。[1] 但在这里简要描述一下。在访问 1 中，我们在每个参与者的头上放了一个塑料帽，并使用闭环 TMS 运动诱发电位 (MEP) 采集设置，使用 TMS 单脉冲（Magstim BiStim 机器，带有 70 毫米八字形远程线圈；惠特兰，威尔士， UK) 在对侧右手上的左侧运动热点和肌电图 (EMG) 电极上 [5]。我们将正 MEP 定义为峰峰值幅度为 0.05mV，并使用 PEST 软件 (https://www. Clinicalresearcher.org/software.htm) 以确定 MT 采集的下一个刺激强度 [6]。确定 TMS MT 后，我们切开塑料盖以放置 35 20mm 电极（Natus Neurology Inc., Pleasanton, CA, USA）