Feeling Unreal:Depersonalization Disorder and the Loss of the Self by Simeon Daphne & Jeffrey Abugel

Author:Simeon, Daphne & Jeffrey Abugel [Simeon, Daphne]
Language: eng
Format: mobi
Publisher: Oxford University Press
Published: 2008-10-10T04:00:00+00:00

The Autonomic System and Norepinephrine

The autonomic system is the part of the nervous system that regulates basic organ processes needed to maintain normal bodily functions, such as heart rate and blood pressure, and it is of particular interest in dissociation. In some psychiatric disorders associated with high levels of anxiety and arousal, such as panic disorder and PSTD, the autonomic system is hyperactive. In contrast, there is some emerging evidence that in dissociative states the autonomic system might be hypoactive. For example, decreased heart rate and galvanic skin responses have been reported in women who experienced strong dissociation after being raped.31

Specifically in DPD, there is limited but possibly compelling evidence for autonomic hyporeactivity. Mauricio Sierra and his colleagues in the UK published a study in 2002 that measured galvanic skin responses in DPD.32 Galvanic skin responses indicate a change in the electrical properties of the skin in response to stress or anxiety and can be measured by recording the electrical resistance of the skin. Sierra et al. found that in response to emotionally unpleasant stimuli, DPD participants exhibited reduced magnitude and increased delay of skin conductance responses compared to people with anxiety disorders and healthy individuals. On one hand, the findings indicated that the DPD group was less aroused and had weaker autonomic responses to these emotional stimuli compared to the other two groups. On the other hand, the DPD group did not show diminished galvanic skin responses to non-specific stimuli, such as the sounds of a clap or a sigh, suggesting that what is occurring in DPD may be a particular selective inhibition of emotional responsiveness. As we’ve discussed throughout, this hypoemotionality appears to be one of the core features of the disorder.

The noradrenergic system is a stress-responsive neurochemical system that uses norepinephrine, an adrenaline-like substance, as its chemical messenger. Norepinephrine is central to facilitating alertness, orientation toward new stimuli, selective attention, and enhanced memory encoding under stressful conditions. In other words, when we are stressed either internally or by our environment, norepinephrine helps us focus our attention and remember new and emotional occurrences, ensuring better survival and adaptation to ever-changing environments. However, although bursts in norepinephrine activity under acute stress are adaptive, more chronic noradrenergic activation “for no good reason,” such as that encountered in certain psychiatric conditions related to traumatic stress, is maladaptive. For example, there are a number of studies showing a heightened noradrenergic tone in people with PTSD, which goes hand in hand with the hyperarousal and intrusive symptoms.

Although norepinephrine has not been extensively studied in dissociation, there are some revealing recent studies. Dissociative patients, in a sense, present with symptoms that are opposite those in classic PTSD: instead of being hyperaroused, they’re “shut down.”33 One could therefore speculate that dissociative patients exhibit a noradrenergic dysfunction of an opposite type than classic PTSD. Indeed, there are now three small studies that have found a relationship between lower norepinephrine and dissociation. Simeon’s group found that in people with DPD, norepinephrine in a urine sample collected over 24 hours was strongly inversely correlated with the severity of dissociation.

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