Amygdala activation and its functional connectivity during perception of emotional faces in social phobia and panic disorder

Social phobia (SP) and panic disorder (PD) have been associated with aberrant amygdala responses to threat-related stimuli. The aim of the present study was to examine amygdala function and its connectivity with medial prefrontal cortex (mPFC) during emotional face perception in PD and SP, and the role of illness severity. Blood oxygen level dependent responses while perceiving emotional facial expressions were compared in 14 patients with PD, 17 patients with SP, 8 patients with comorbid PD and SP, and 16 healthy controls. We found that PD, but not SP, was associated with amygdala and lingual gyrus hypoactivation during perception of angry, fearful, happy and neutral faces, compared to healthy participants. No significant effect of PD and SP diagnoses was found on amygdala-mPFC connectivity. A positive correlation of anxiety symptom severity was found on amygdala-dorsal anterior cingulate and dorsal mPFC connectivity during perception of fearful faces. Amygdala hypoactivation suggests reduced responsiveness to positive and negative emotional faces in PD. Symptom severity, but not the presence of PD and SP diagnosis per se, explains most of the abnormalities in amygdala-mPFC connectivity during perception of fearful faces.