Authors
Rohira, V., Coxon, J., Stevens, K., Joshi, R., Thirugnanasambandam, N., Leunissen, I., Chong, T., Bellgrove, M.
Abstract
Inhibitory control is an essential executive function that encompasses both the stopping of an action in response to an unexpected stop signal (reactive response inhibition) and slowing of responses in anticipation of stopping (proactive response inhibition). Fronto-basal-ganglia circuits are thought to differentially contribute to response inhibition, with the indirect pathway implicated in proactive inhibition. Given the high expression of dopamine D2 receptors in the indirect pathway, pharmacological blockade of D2 receptors is expected to impact proactive inhibition, as indicated by response times on Go trials. The current study aimed to investigate this experimentally and study the effect of 600 mg of sulpiride, a D2 receptor antagonist, on behavioural and electrophysiological measures of proactive and reactive inhibition in humans. Human participants (N=24) completed an anticipated response version of the stop-signal task on either sulpiride or placebo in a double-blind within-subjects design. Sulpiride led to increased variability of Go response times and attenuation of the frontocentral negativity/readiness potential, considered to be a signature of proactive inhibition. In contrast, sulpiride had no effect on stop-signal reaction time or event-related potential components associated with reactive inhibition. These findings suggest that D2 receptor blockade selectively alters processes involved in proactive inhibition while leaving reactive inhibition unaffected, consistent with a key role for the indirect basal ganglia pathway in proactive response inhibition.
Preprint server:
bioRxiv
The authors list and abstract were imported from bioRxiv on 23 Sep 2026.
Advertisement
Stats
- Recommendations n/a n/a positive of 0 vote(s)
- Views 13
- Comments 0