Cortico-basal ganglia dynamics of global and selective response inhibition in humans

Overview

Response inhibition lets people stop inappropriate actions. Prior work focused on simple, all-or-none stopping. Real-world stopping is selective: only certain signals should be heeded and only some movements should be stopped while others continue. We tested how the fronto-subthalamic circuit implements both global and selective inhibition in humans by recording subthalamic local field potentials and scalp EEG during a task that required stopping all responses, stopping some responses, or ignoring a signal.

Methods

Participants with implanted electrodes in the subthalamic nucleus performed a novel task where salient signals could mean stop-all, stop-some, or ignore. We recorded subthalamic local field potentials and simultaneous scalp EEG to track neural dynamics. We analyzed rapid changes in β-band bursting and coupling between frontal cortex and subthalamic nucleus, and compared timing and duration of these signals across the three signal types.

Key results

All salient signals produced an immediate, shared fronto-subthalamic inhibitory response marked by a rapid rise in β-burst activity. When the signal required stopping all actions, subthalamic β-bursting increased further and remained elevated for over a second. For selective stopping (stop only some responses), the elevated β activity was delayed and shorter, allowing a timely release of inhibition so that permitted movements could continue. Frontal cortical and subthalamic β-band activity were tightly coupled throughout these periods.

Implications

Selective inhibition operates by a fast, context-dependent engagement and then rapid release of fronto-subthalamic inhibition rather than by an all-or-none mechanism. The subthalamic inhibitory signal can persist far longer than behavioral models typically assume, supporting newer theories that propose prolonged inhibitory control during action stopping. These findings bridge simple laboratory paradigms and the more nuanced demands of real-world control, with implications for understanding and treating disorders of inhibitory control.