University of Sydney, Camperdown, NSW, 2006.
University of Sydney, Camperdown, NSW, 2006.
Neuroscience. 2019 Sep 1;415:10-17. doi: 10.1016/j.neuroscience.2019.07.013. Epub 2019 Jul 11.
We have recently shown that the efficiency of stopping a response is correlated with GABAergic activity in primary motor cortex (M1) measured using the short interval intracortical inhibition (SICI) protocol. However, this finding was observed when SICI was measured in left M1 and when stopping efficiency was measured with a bimanual response task. The aim of the present study was to examine the extent to which the relationship between SICI and stopping is lateralized to the hemisphere controlling the response (e.g. left M1 and stopping a right hand response) and/or reflects bilateral inhibitory mechanisms (as might be seen between left M1 and left hand stopping). We measured resting SICI (i.e. during relaxed muscle activity) in left and right M1 and stopping efficiency in the left and right hand, in 38 healthy individuals. We found that SICI was significantly correlated between hemispheres (r = 0.51) and stopping efficiency was correlated between hands (r = 0.77). When controlling for other relevant variables, we found that stopping efficiency in each hand was uniquely predicted by SICI in the contralateral hemisphere, but not the ipsilateral hemisphere. These results suggest that there is a hemispheric-specific contribution of SICI to stopping efficiency.
我们最近发现，使用短间隔皮质内抑制（SICI）方案测量的初级运动皮层（M1）中的 GABA 能活性与反应停止的效率相关。然而，这一发现是在测量左 M1 中的 SICI 并在手的双侧反应任务中测量停止效率时观察到的。本研究的目的是检验 SICI 与停止之间的关系在多大程度上偏向于控制反应的大脑半球（例如，左 M1 和停止右手反应），或者反映双侧抑制机制（例如，左 M1 和左手停止之间可能出现的情况）。我们在 38 名健康个体中测量了左、右 M1 的静息 SICI（即肌肉放松时的 SICI）和左手、右手的停止效率。我们发现，半球间 SICI 呈显著相关（r=0.51），手间停止效率呈显著相关（r=0.77）。当控制其他相关变量时，我们发现，每只手的停止效率都可由对侧半球的 SICI 独特预测，但不能由同侧半球预测。这些结果表明，SICI 对停止效率的贡献具有半球特异性。
