Oxytocin Modulates Inhibitory Control via Neural-Temporal Mechanisms

Inhibitory control is frequently impaired under anxiety, yet the temporal dynamics through which oxytocin (OXT) modulates this process remain poorly understood. This randomized, double-blind, placebo-controlled pharmacological event-related potential (ERP) study investigated how intranasal OXT (24 IU) influences neural and behavioral correlates of inhibitory control under threat-of-shock (anxiety) and safe conditions in 100 healthy male university students. Participants performed an interference-inhibition working memory task requiring attention to either emotional faces (social) or house scenes (non-social) while ignoring superimposed task-irrelevant stimuli. ERPs across distinct processing stages (N1, P2, N2, N450) were analyzed. OXT did not significantly affect behavioral performance. However, it produced stage-specific, context-dependent neuromodulatory effects. Specifically, OXT (1) modulated early perceptual processing of social stimuli under anxiety, as indicated by a reduced P2 amplitude to faces; (2) influenced conflict-monitoring, as reflected by an anxiety-dependent attenuation of the N2 response during the non-social task; and (3) modulated later conflict resolution processes, evidenced by a double dissociation in the N450 component: OXT prevented the anxiety-induced increase in N450 for houses while enhancing the N450 response to faces under threat. This study provides temporal insights into the neurophysiological effects of OXT, indicating that OXT modulates inhibitory control through multi-stage neural processes rather than a general anxiolytic effect.