Depersonalization disorder commonly includes apparently physical symptoms and disturbances in perception, such as a sense of numbness, a feeling of having a head full of cotton, a difficult-to-describe detachment from one’s body, and a perception of objects as flattened or larger or smaller than they are. Many of these symptoms may be explained by increasing evidence of distinct physiological signs exhibited by those with depersonalization disorder, including autonomic irregularities and difficulties with self-perception. These physiological differences may also be involved in the altered experiences of emotion that are characteristic of depersonalization.
- Sierra et al. (2002) found that subjects with depersonalization disorder showed a reduced skin conductance response to stimuli compared to healthy controls and subjects with anxiety disorders. Those with depersonalization disorder were also significantly less likely to show a response to unpleasant stimuli, and the latency of their response to unpleasant stimuli was increased. The authors conclude that subjects with depersonalization “show a trend suggesting generalized hyporesponsiveness”: “In fact, there is no differential responding by patients with depersonalization disorder to unpleasant pictures compared with pleasant and neutral pictures. The absence of any differential SCR to these types of emotional stimuli is striking; higher amplitude SCRs to unpleasant stimuli were found in controls and those with anxiety disorders.” At the same time, subjects with depersonalization and anxiety disorders both showed a faster reaction to physical stimuli such as clapping, “suggestive of a state of heightened arousal”.
- Schoenberg, Sierra, & David (2012) found that patients with depersonalization disorder showed “abnormally high sympathetic lability” compared to healthy controls and exhibited more nonspecific skin conductance responses. The authors noted that elevated skin conductance levels may also explain a “cognitive hypervigilance”.
