Action-stopping is a canonical executive function thought to involve top-down control over the motor system. Here we aimed to validate this stopping system using high temporal resolution methods in humans. We show that, following the requirement to stop, there was an increase of right frontal beta (~13 to 30 Hz) at ~120 ms, likely a proxy of right inferior frontal gyrus; then, at 140 ms, there was a broad skeletomotor suppression, likely reflecting the impact of the subthalamic nucleus on basal ganglia output; then, at ~160 ms, suppression was detected in the muscle, and, finally, the behavioral time of stopping was ~220 ms. This temporal cascade supports a physiological model of action-stopping, and partitions it into subprocesses that are isolable to different nodes and are more precise than the behavioral latency of stopping. Variation in these subprocesses, including at the single-trial level, could better explain individual differences in impulse control.
- Sumitash Jana
- Ricci Hannah
- Vignesh Muralidharan
- Adam R Aron
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: All human volunteers provided written informed consent prior to their participation. The participants were compensated at $20/hour. The University of California San Diego Institutional Review Board approved all the studies (protocol #171285).
- Wery van den Wildenberg, Universiteit van Amsterdam, Netherlands
© 2020, Jana et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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