پاسخ اتونوم در برداشت از انزجار و شادی در اختلال مسخ شخصیت

Patients with depersonalization disorder have shown attenuated responses to emotional unpleasant stimuli, hence supporting the view that depersonalization is characterised by a selective inhibition on the processing of unpleasant emotions. It was the purpose of this study to establish if autonomic responses to facial emotional expressions also show the same blunting effect. The skin conductance responses (SCRs) of 16 patients with chronic DSM-IV depersonalization disorder, 15 normal controls and 15 clinical controls with DSM-IV anxiety disorders were recorded in response to facial expressions of happiness and disgust. Patients with anxiety disorders were found to have greater autonomic responses than patients with depersonalization, in spite of the fact that both groups had similarly high levels of subjective anxiety as measured by anxiety scales. SCR to happy faces did not vary across groups. The findings of this study provide further support to the idea that patients with depersonalization have a selective impairment in the processing of threatening or unpleasant emotional stimuli.

Depersonalization disorder is characterised by persistent or recurrent episodes of ‘detachment or estrangement from one's self.’ The individual may feel like an automaton or there may be the sensation of being an outside observer of one's own mental processes (American Psychiatric Association, 1994). Depersonalization has been shown to correlate with anxiety measures, and most patients with a diagnosis of depersonalization disorder (DPD) have been shown to have significant levels of anxiety or comorbid anxiety disorders (Simeon et al., 2003a and Baker et al., 2003). This, together with the high prevalence of depersonalization at times of life threatening situations, has been interpreted as suggesting that depersonalization represents an anxiety-triggered ‘hard wired’ inhibitory response intended to ensure the preservation of adaptative behaviour during situations normally associated with overwhelming and potentially disorganizing anxiety (Sierra and Berrios, 1998). In such circumstances, it has been suggested that depersonalization will result in the inhibition of non-functional emotional and autonomic responses whilst maintaining vigilant attention. In patients with DPD this response would become abnormally persistent and dysfunctional ( Sierra and Berrios, 1998). Recent fMRI (Phillips et al., 2001) and psychophysiological studies (Sierra et al., 2002) support the above model and have indicated that patients with DPD show lack of activation in limbic areas, and marked autonomic attenuation in response to pictures depicting disgusting or distressing situations. In the same vein Lanius et al. (2002) recently studied patients with sexual-abuse-related posttraumatic stress disorder and found that, while 70% of patients had increased heart rate during a traumatic script-driven symptom provocation, those patients who had a dissociative response (30%) during the experiment did not show any concomitant increase in heart rate. Also supporting an anxiety-suppressing mechanism in depersonalization, is the finding by Simeon et al. (2003b) of a striking negative correlation (r = − 0.8) between intensity of depersonalization and urine norepinephrine levels. In view of the fact that some facial emotional expressions can signal threatening situations to others (e.g. fear or disgust), it was hypothesised that patients with DPD would have selectively attenuated SCR to facial expressions of negative emotions as compared to facial expressions of positive emotions (e.g. happiness). In fact, given that perception of positive emotions is usually a safety signal to others, SCR responses to happy expressions was predicted to be normal in the DPD group. To test these predictions we compared event related SCRs to visual presentations of genuine (as opposed to posed) facial expressions of disgust and happiness, in patients with DPD and two control groups: normal controls, and patients with a diagnosis of an anxiety disorder.