Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina, USA.
Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, USA.
Sci Rep. 2018 Feb 19;8(1):3253. doi: 10.1038/s41598-018-21634-0.
Transcranial magnetic stimulation (TMS) can stimulate cortical and subcortical brain regions. However, in order to reach subcortical targets, intact monosynaptic connections are required. The goal of this investigation was to evaluate the contribution of white matter integrity and gray matter volume to frontal pole TMS-evoked striatal activity in a large cohort of chronic cocaine users. 49 cocaine users received single pulses of TMS to the frontal pole while BOLD data were acquired - a technique known as interleaved TMS/fMRI. Diffusion tensor imaging and voxel-based morphometry were used to quantify white matter integrity and gray matter volume (GMV), respectively. Stepwise regression was used to evaluate the contribution of clinical and demographic variables to TMS-evoked BOLD. Consistent with previous studies, frontal pole TMS evoked activity in striatum and salience circuitry. The size of the TMS-evoked response was related to fractional anisotropy between the frontal pole and putamen and GMV in the left frontal pole and left ACC. This is the first study to demonstrate that the effect of TMS on subcortical activity is dependent upon the structural integrity of the brain. These data suggest that these structural neuroimaging data types are biomarkers for TMS-induced mobilization of the striatum.
经颅磁刺激（TMS）可刺激皮质和皮质下脑区。然而，为了达到皮质下靶点，需要完整的单突触连接。本研究旨在评估白质完整性和灰质体积对慢性可卡因使用者大样本中额极 TMS 诱发纹状体活动的贡献。49 名可卡因使用者接受额极单脉冲 TMS 刺激，同时采集 BOLD 数据——一种称为交叠 TMS/fMRI 的技术。弥散张量成像和基于体素的形态计量学分别用于量化白质完整性和灰质体积（GMV）。逐步回归用于评估临床和人口统计学变量对 TMS 诱发 BOLD 的贡献。与之前的研究一致，额极 TMS 诱发了纹状体和突显回路的活动。TMS 诱发反应的大小与额极和壳核之间的各向异性分数以及左侧额极和左侧 ACC 的 GMV 相关。这是第一项表明 TMS 对皮质下活动的影响取决于大脑结构完整性的研究。这些数据表明，这些结构神经影像学数据类型是 TMS 诱导纹状体运动的生物标志物。
