Cerebral and autonomic responses to emotional facial expressions in depersonalisation disorder

BACKGROUND: Depersonalisation disorder is characterised by emotion suppression, but the cerebral mechanisms of this symptom are not yet fully understood. AIMS: To compare brain activation and autonomic responses of individuals with the disorder and healthy controls. METHOD: Happy and sad emotion expressions in increasing intensities (neutral to intense) were presented in an implicit event-related functional magnetic resonance imaging (fMRI) design with simultaneous measurement of autonomic responses. RESULTS: Participants with depersonalisation disorder showed fMRI signal decreases, whereas the control group showed signal increases in response to emotion intensity increases in both happy and sad expressions. The analysis of evoked haemodynamic responses from regions exhibiting functional connectivity between central and autonomic nervous systems indicated that in depersonalisation disorder initial modulations of haemodynamic response occurred significantly earlier (2 s post-stimulus) than in the control group (4-6 s post-stimulus). CONCLUSIONS: The results suggest that fMRI signal decreases are possible correlates of emotion suppression in depersonalisation disorder.