Fronto-striato-limbic hyperactivation in obsessive-compulsive disorder during individually tailored symptom provocation

Anxiety disorders have been linked to a hyperactivated cortico-amygdalar circuitry, but the amygdala's role in the pathophysiology of obsessive-compulsive disorder (OCD) remains unclear. This fMRI study examined the cortico-limbic correlates of individually tailored symptom provocation in 14 unmedicated OCD patients and 14 controls. In addition to OCD-relevant pictures, aversive and neutral control stimuli were included. Patients showed increased fronto-striatal activation to OCD-relevant stimuli contrasted with both control categories. Briefly presented symptom-related triggers elicited stronger amygdala engagement in patients than in controls. This effect, however, did also occur to aversive stimuli and was not symptom specific. Augmented amygdala involvement in patients reflects general emotional hyperarousal. Symptom-specific frontal activation points towards a sustained endeavor to suppress exaggerated emotional responses to OCD triggers.