Stopping actions depends on the integrity of the right inferior frontal gyrus (rIFG). Electrocorticography from the rIFG shows an increase in beta power during action-stopping. Scalp EEG shows a similar right frontal beta increase, but it is unknown if this beta modulation relates to the underlying rIFG network. Demonstrating a causal relationship between the rIFG and right frontal beta in EEG during action-stopping is important for putting this electrophysiological marker on a firmer footing. In a double-blind study with a true sham coil, we used fMRI-guided 1Hz repetitive transcranial magnetic stimulation (rTMS) to disrupt the rIFG, and to test if this eroded right frontal beta and impaired action-stopping. We found that rTMS selectively slowed stop signal reaction time (SSRT) (no effect on Go), and reduced right frontal beta (no effect on sensorimotor mu/beta related to Go); it also reduced the variance of a single trial muscle marker of stopping. Surprisingly, sham also slowed SSRTs and reduced beta. Part of this effect, however, resulted from carry-over of real stimulation in participants who received real first. A post-hoc between-group comparison of those participants who received real first compared to those who received sham first showed that real stimulation eroded beta significantly more. Thus, real rTMS uniquely affected metrics of stopping in the muscle and resulted in a stronger erosion of beta. We argue that this causal test validates right frontal beta as a functional marker of action-stopping.

中文翻译：

---

用 TMS 双盲破坏右下额叶皮层可降低右额叶 β 功率以停止行动


停止动作取决于右额下回（rIFG）的完整性。 rIFG 的皮层电图显示，动作停止期间 β 功率增加。头皮脑电图显示类似的右额叶 β 增加，但尚不清楚这种 β 调节是否与底层 rIFG 网络有关。证明动作停止期间脑电图中 rIFG 与右额叶 β 之间的因果关系对于使这一电生理标记有更坚实的基础非常重要。在一项使用真假线圈的双盲研究中，我们使用功能磁共振成像引导的 1Hz 重复经颅磁刺激 (rTMS) 来破坏 rIFG，并测试这是否会侵蚀右额叶β并损害动作停止。我们发现rTMS选择性地减慢停止信号反应时间（SSRT）（对Go没有影响），并减少右额叶β（对与Go相关的感觉运动mu/beta没有影响）；它还减少了停止时单个试验肌肉标记的方差。令人惊讶的是，假手术还减慢了 SSRT 并降低了 beta。然而，这种效应的部分原因是首先接受真实刺激的参与者继承了真实刺激。对首先接受真实刺激的参与者与首先接受假刺激的参与者进行的事后组间比较表明，真实刺激对β的侵蚀显着更大。因此，真正的 rTMS 独特地影响了肌肉停止的指标，并导致了更强烈的 β 侵蚀。我们认为，这个因果测试验证了右额叶贝塔作为行动停止的功能标记。