We have recently shown that the efficiency in stopping a response, measured using the stop signal task, is related to GABA_A-mediated short-interval intracortical inhibition (SICI) in the primary motor cortex. In this study, we conducted two experiments on humans to determine whether training participants in the stop signal task within one session (Experiment 1) and across multiple sessions (Experiment 2) would increase SICI strength. For each experiment, we obtained premeasures and postmeasures of stopping efficiency and resting-state SICI, that is, during relaxed muscle activity (Experiment 1, n = 45, 15 male participants) and SICI during the stop signal task (Experiment 2, n = 44, 21 male participants). In the middle blocks of Experiment 1 and the middle sessions of Experiment 2, participants in the experimental group completed stop signal task training, whereas control participants completed a similar task without the requirement to stop a response. After training, the experimental group showed increased resting-state SICI strength (Experiment 1) and increased SICI strength during the stop signal task (Experiment 2). Although there were no overall behavioral improvements in stopping efficiency, improvements at an individual level were correlated with increases in SICI strength at rest (Experiment 1) and during successful stopping (Experiment 2). These results provide evidence of neuroplasticity in resting-state and task-related GABA_A-mediated SICI in the primary motor cortex after response inhibition training. These results also suggest that SICI and stopping efficiency are temporally linked, such that a change in SICI between time points is correlated with a change in stopping efficiency between time points.

我们最近表明，使用停止信号任务测量的停止响应的效率与初级运动皮层中GABA _A介导的短间隔皮质内抑制 (SICI) 相关。在这项研究中，我们对人类进行了两项实验，以确定在一个会话（实验 1）和多个会话（实验 2）内训练参与者停止信号任务是否会增加 SICI 强度。对于每个实验，我们获得了停止效率和静息状态 SICI 的前测和后测，即放松肌肉活动期间（实验 1，n = 45，15 名男性参与者）和停止信号任务期间的 SICI（实验 2，n= 44, 21 名男性参与者）。在实验 1 的中间区块和实验 2 的中间阶段，实验组的参与者完成了停止信号任务训练，而对照组的参与者完成了类似的任务，而无需停止响应。训练后，实验组表现出增加的静息状态 SICI 强度（实验 1）和增加的停止信号任务期间的 SICI 强度（实验 2）。尽管停止效率没有整体行为改善，但个体水平的改善与休息时（实验 1）和成功停止（实验 2）期间 SICI 强度的增加相关。这些结果提供了静息状态和任务相关 GABA _A中神经可塑性的证据反应抑制训练后初级运动皮层介导的 SICI。这些结果还表明 SICI 和停止效率在时间上是相关的，因此时间点之间 SICI 的变化与时间点之间停止效率的变化相关。