US CCDC Army Research Laboratory, 459 Mulberry Pt Rd., Aberdeen Proving Ground, MD, 21005, USA.
University of Pennsylvania, Philadelphia, PA, USA.
Sci Rep. 2020 Sep 10;10(1):14890. doi: 10.1038/s41598-020-71692-6.
Visual attentive tracking requires a balance of excitation and inhibition across large-scale frontoparietal cortical networks. Using methods borrowed from network science, we characterize the induced changes in network dynamics following low frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) as an inhibitory noninvasive brain stimulation protocol delivered over the intraparietal sulcus. When participants engaged in visual tracking, we observed a highly stable network configuration of six distinct communities, each with characteristic properties in node dynamics. Stimulation to parietal cortex had no significant impact on the dynamics of the parietal community, which already exhibited increased flexibility and promiscuity relative to the other communities. The impact of rTMS, however, was apparent distal from the stimulation site in lateral prefrontal cortex. rTMS temporarily induced stronger allegiance within and between nodal motifs (increased recruitment and integration) in dorsolateral and ventrolateral prefrontal cortex, which returned to baseline levels within 15 min. These findings illustrate the distributed nature by which inhibitory rTMS perturbs network communities and is preliminary evidence for downstream cortical interactions when using noninvasive brain stimulation for behavioral augmentations.
视觉注意跟踪需要在大范围的额顶皮质网络中平衡兴奋和抑制。我们使用从网络科学借来的方法，描述了低频（1Hz）重复经颅磁刺激（rTMS）作为一种抑制性的无创脑刺激方案，在顶内沟施加后，网络动力学的诱导变化。当参与者进行视觉跟踪时，我们观察到六个不同社区的高度稳定的网络配置，每个社区都具有节点动力学的特征属性。刺激顶叶皮层对顶叶社区的动力学没有显著影响，与其他社区相比，该社区已经表现出了更高的灵活性和混杂性。然而，rTMS 的影响在刺激部位的远侧在外侧前额叶皮层中是明显的。rTMS 在背外侧和腹外侧前额叶皮层中暂时诱导了更强的节点内和节点间模式（增加募集和整合）的忠诚性，在 15 分钟内恢复到基线水平。这些发现说明了抑制性 rTMS 扰乱网络社区的分布式性质，并且当使用无创脑刺激进行行为增强时，这是下游皮质相互作用的初步证据。
