Feeling unreal: A PET study of depersonalization disorder

Objective: The goal of this study was to assess brain glucose metabolism an d its relationship to dissociation measures and clinical symptoms in DSM-IV depersonalization disorder. Method: Positron emission tomography scans coregistered with magnetic reson ance images of eight subjects with depersonalization disorder were compared to those of 24 healthy comparison subjects. The two groups did not differ in age, sex, education, performance on a baseline neuropsychological batter y, or performance on a verbal learning task administered during [F-18]fluor odeoxyglucose uptake. A cortical analysis by individual Brodmann's areas wa s performed. Results: Compared to the healthy subjects, subjects with depersonalization disorder showed significantly lower metabolic activity in Fight Brodmann's areas 22 and 21 of the superior and middle temporal gyri and had significan tly higher metabolism in parietal Brodmann's areas 7B and 39 and left occip ital Brodmann's area 19. Dissociation and depersonalization scores among th e subjects with depersonalization disorder were significantly positively co rrelated with metabolic activity in area 7B. Conclusions: Depersonalization appears to be associated with functional abn ormalities along sequential hierarchical areas, secondary and cross-modal, of the sensory cortex (visual, auditory, and somatosensory), as well as are as responsible for an integrated body schema. These findings are in good ag reement with the phenomenological conceptualization of depersonalization as a dissociation of perceptions as well as with the subjective symptoms of d epersonalization disorder.