Gogulski Juha, Cline Christopher C, Ross Jessica M, Truong Jade, Sarkar Manjima, Parmigiani Sara, Keller Corey J
Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA; Department of Clinical Neurophysiology, HUS Diagnostic Center, Clinical Neurosciences, Helsinki University Hospital and University of Helsinki, Helsinki, FI-00029 HUS, Finland.
Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA.
Clin Neurophysiol. 2024 Aug;164:138-148. doi: 10.1016/j.clinph.2024.05.008. Epub 2024 May 27.
Transcranial magnetic stimulation (TMS) to the dorsolateral prefrontal cortex (dlPFC) is an effective treatment for depression, but the neural effects after TMS remains unclear. TMS paired with electroencephalography (TMS-EEG) can causally probe these neural effects. Nonetheless, variability in single pulse TMS-evoked potentials (TEPs) across dlPFC subregions, and potential artifact induced by muscle activation, necessitate detailed mapping for accurate treatment monitoring.
To characterize early TEPs anatomically and temporally (20-50 ms) close to the TMS pulse (EL-TEPs), as well as associated muscle artifacts (<20 ms), across the dlPFC. We hypothesized that TMS location and angle influence EL-TEPs, and specifically that conditions with larger muscle artifact may exhibit lower observed EL-TEPs due to over-rejection during preprocessing. Additionally, we sought to determine an optimal group-level TMS target and angle, while investigating the potential benefits of a personalized approach.
In 16 healthy participants, we applied single-pulse TMS to six targets within the dlPFC at two coil angles and measured EEG responses.
Stimulation location significantly influenced observed EL-TEPs, with posterior and medial targets yielding larger EL-TEPs. Regions with high EL-TEP amplitude had less muscle artifact, and vice versa. The best group-level target yielded 102% larger EL-TEP responses compared to other dlPFC targets. Optimal dlPFC target differed across subjects, suggesting that a personalized targeting approach might boost the EL-TEP by an additional 36%.
EL-TEPs can be probed without significant muscle-related confounds in posterior-medial regions of the dlPFC. The identification of an optimal group-level target and the potential for further refinement through personalized targeting hold significant implications for optimizing depression treatment protocols.
经颅磁刺激（TMS）作用于背外侧前额叶皮质（dlPFC）是治疗抑郁症的一种有效方法，但TMS后的神经效应仍不清楚。TMS与脑电图（TMS-EEG）相结合可以因果性地探究这些神经效应。然而，dlPFC各亚区域单脉冲TMS诱发电位（TEP）的变异性以及肌肉激活引起的潜在伪迹，需要进行详细的图谱绘制以实现准确的治疗监测。
在dlPFC区域，从解剖学和时间上（在TMS脉冲后20 - 50毫秒）表征早期TEP（EL-TEP）以及相关的肌肉伪迹（<20毫秒）。我们假设TMS的位置和角度会影响EL-TEP，具体而言，由于预处理过程中的过度剔除，肌肉伪迹较大的情况下观察到的EL-TEP可能较低。此外，我们试图确定最佳的组水平TMS靶点和角度，同时研究个性化方法的潜在益处。
在16名健康参与者中，我们以两个线圈角度对dlPFC内的六个靶点施加单脉冲TMS，并测量脑电图反应。
刺激位置显著影响观察到的EL-TEP，后部和内侧靶点产生的EL-TEP更大。EL-TEP振幅高的区域肌肉伪迹较少，反之亦然。与其他dlPFC靶点相比，最佳的组水平靶点产生的EL-TEP反应大102%。最佳的dlPFC靶点因个体而异，这表明个性化靶向方法可能会使EL-TEP再提高36%。
在dlPFC的后内侧区域可以探测到EL-TEP，而不会受到明显的肌肉相关干扰。确定最佳的组水平靶点以及通过个性化靶向进一步优化的潜力，对优化抑郁症治疗方案具有重要意义。
