Psychological distress modulates dorsal anterior cingulate cortex responses to salient stimuli in obsessive-compulsive disorder

Background: Patients with obsessive-compulsive disorder (OCD) experience an exacerbation of symptoms under psychological distress. The neurobiological underpinnings of this effect of stress remain elusive. Here, we induced psychological distress to explore its effect on neural reactivity of the salience network during a symptom provocation task. Methods: Twenty-three patients with OCD and twenty-three healthy volunteers underwent functional magnetic resonance imaging scanning after stress induction and a control condition in a cross-over design. Psychological distress was induced using the socially evaluated cold pressor test (SECPT) and neural responses were measured during a symptom provocation task. Results: OCD participants showed a blunted cortisol response to the stressor. We found a group by stress interaction effect in the dorsal anterior cingulate cortex (dACC), such that psychological distress reduced dACC reactivity to emotionally salient pictures in OCD participants, whereas it increased dACC reactivity in healthy controls. Limitations: A considerable proportion of OCD participants was on medication, and the neuroimaging session was conducted more than 1 h after the initial stressor. Conclusions: Considering this timeline, we speculate that the blunted dACC reactivity towards emotionally salient pictures in OCD participants may reflect impaired emotion regulation in the aftermath of stress.