Objectives. The abnormal processing of emotional stimuli is common to a variety of psychiatric disorders. Specifically, patients with prominent anxiety symptoms generally overreact to emotional cues, which has been linked to increased amygdala activation. However, in OCD, enhanced responses are predominantly obtained using disease-specific stimuli and preferentially involve frontostriatal systems. Methods. We assessed 21 OCD patients and 21 healthy controls with fMRI during an emotional face-processing paradigm involving active response generation to test for alterations in both brain activation and task-induced functional connectivity of the frontal cortex, the amygdala and the fusiform face area. Results. OCD patients showed significantly greater activation of "â€œface-processing"â€ regions including the amygdala, fusiform gyrus and dorsolateral prefrontal cortex. The reciprocal connectivity between face-processing regions was enhanced in OCD. Importantly, we detected significant correlations between patients'â€(tm) clinical symptom severity and both task-related region activation and network functional connectivity. Conclusions. The results suggest that OCD patients may show enhanced brain responsiveness during emotional face-processing when tasks involve active response generation. Our findings diverge from previously described alterations in anxiety disorders, as patients showed enhanced amygdala-prefrontal connectivity as opposed to negative reciprocal interaction. This pattern would appear to be disorder-specific and was significantly related to obsessive-compulsive symptom severity. © 2011 Informa Healthcare.
- Functional imaging
- Obsessive-compulsive disorder
- Prefrontal cortex