Uncomfortably numb : new evidence for suppressed emotional reactivity in response to body-threats in those predisposed to sub-clinical dissociative experiences

摘要

Introduction: Depersonalization and derealization disorders refer to feelings of detachment and dissociation from one’s ‘self’ or surroundings. A reduced sense of self (or ‘presence’) and emotional ‘numbness’ is thought to be mediated by aberrant emotional processing due to biases in self-referent multi-sensory integration. This emotional ‘numbing’ is often accompanied by suppressed autonomic arousal to emotionally salient stimuli. \udMethods: 118 participants completed the Cambridge Depersonalization scale (Sierra & Berrios, 2000) as an index of dissociative anomalous experience. Participants took part in a novel ‘Implied Body-Threat Illusion’ task; a pantomimed injection procedure conducted directly onto their real body (hand). Objective psychophysiological data were recorded via standardised threat-related skin conductance responses and finger temperature measures. \udResults: Individuals predisposed to depersonalization / derealization revealed suppressed skin conductance responses towards the pantomimed body-threat. Although the task revealed a reliable reduction in finger temperature as a fear response, this reduction was not reliably associated with measures of dissociative experience. \udConclusions: The present findings significantly extend previous research by revealing emotional suppression via a more direct body-threat task, even for sub-clinical groups. The findings are discussed within probabilistic and predictive-coding frameworks of multisensory integration underlying a coherent sense of self.