Transcranial Magnetic Stimulation Reveals Dissociable Mechanisms for Global Versus Selective Corticomotor Suppression Underlying the Stopping of Action

Abstract

Stopping an initiated response is an essential function, investigated in many studies with go/no-go and stop-signal paradigms. These standard tests require rapid action cancellation. This appears to be achieved by a suppression mechanism that has "global" effects on corticomotor excitability (i.e., affecting task-irrelevant muscles). By contrast, stopping action in everyday life may require selectivity (i.e., targeting a specific response tendency without affecting concurrent action). We hypothesized that while standard stopping engages global suppression, behaviorally selective stopping engages a selective suppression mechanism. Accordingly, we measured corticomotor excitability of the task-irrelevant leg using transcranial magnetic stimulation while subjects stopped the hand. Experiment 1 showed that for standard (i.e., nonselective) stopping, the task-irrelevant leg was suppressed. Experiment 2 showed that for behaviorally selective stopping, there was no mean leg suppression. Experiment 3 directly compared behaviorally nonselective and selective stopping. Leg suppression occurred only in the behaviorally nonselective condition. These results argue that global and selective suppression mechanisms are dissociable. Participants may use a global suppression mechanism when speed is stressed; however, they may recruit a more selective suppression mechanism when selective stopping is behaviorally necessary and preparatory information is available. We predict that different fronto-basal-ganglia pathways underpin these different suppression mechanisms.

The Role of the Frontal and Parietal Cortex in Proactive and Reactive Inhibitory Control: A Transcranial Direct Current Stimulation Study

“…In particular, reactive inhibitory control seemed to have a "global" effect on corticomotor excitability (Cai, Oldenkamp, & Aron, 2012;Majid, Cai, George, Verbruggen, & Aron, 2012), whereas proactive inhibitory control was more selective (Majid, Cai, Corey-Bloom, & Aron, 2013). It has been suggested that reactive inhibitory control could be implemented via a hyperdirect pathway between the right IFG and the subthalamic nucleus (Aron et al, 2007), resulting in global inhibition (Majid et al, 2013).…”

Complementary roles of cortical oscillations in automatic and controlled processing during rapid serial tasks

“…Decreased excitability was found in task-irrelevant muscles during standard but not selective stopping (Majid et al, 2012). Additional event-related potentials (ERPs) were measured over frontal and parietal regions when stopping in contrast to when changing a motor response in a stop-change task; however these electrophysiological differences were accompanied by behavioural differences in stop or stop-change reaction time (Kramer et al, 2011).…”

Multiple modes of clearing one's mind of current thoughts: Overlapping and distinct neural systems

“…As shown in the third row, only a global clearing of WM requires that all thought be cleared. In the motor domain, neural control mechanisms for global stopping, which is the cessation of all motor responding, are partially distinct from those required to stop a specific motor response (Aron & Verbruggen, 2008; Majid et al, 2012). Analogously, we predict that while some regions required for each of these distinct ways in which information is cleared from working memory will overlap, at least some will also be distinct.…”