Depersonalization disorder Health Article

Definition

Depersonalization is a state in which the individual ceases to perceive the reality of the self or the environment. The patient feels that his or her body is unreal, is changing, or is dissolving; or that he or she is outside of the body.

Depersonalization disorder is classified by the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, text Revision, also known as the DSM-IV-TR as one of the dissociative disorders. These are mental disorders in which the normally well-integrated functions of memory, identity, perception, and consciousness are separated (dissociated). The dissociative disorders are usually associated with trauma in the recent or distant past, or with an intense internal conflict that forces the mind to separate incompatible or unacceptable knowledge, information, or feelings. In depersonalization disorder, the patient's self-perception is disrupted. Patients feel as if they are external observers of their own lives, or that they are detached from their own bodies. Depersonalization disorder is sometimes called "depersonalization neurosis."

Depersonalization as a symptom may occur in panic disorder, borderline personality disorder, post-traumatic stress disorder (PTSD), acute stress disorder, or another dissociative disorder. The patient is not given the diagnosis of depersonalization disorder if the episodes of depersonalization occur only during panic attacks or following a traumatic stressor.

The symptom of depersonalization can also occur in normal individuals under such circumstances as sleep deprivation, the use of certain anesthetics, experimental conditions in a laboratory (experiments involving weightlessness, for example), and emotionally stressful situations (such as taking an important academic examination or being in a traffic accident). One such example involves some of the rescue personnel from the September 11, 2001 terrorist attacks on the World Trade Center and the Pentagon. These individuals experienced episodes of depersonalization after a day and a half without sleep. A more commonplace example is the use of nitrous oxide, or "laughing gas" as an anesthetic during oral surgery. Many dental patients report a sense of unreality or feeling of being outside their bodies during nitrous oxide administration.

To further complicate the matter, depersonalization may be experienced in different ways by different individuals. Common descriptions include a feeling of being outside one's body; "floating on the ceiling looking down at myself" feeling as if one's body is dissolving or changing; feeling as if one is a machine or robot; "unreal" feeling that one is in a dream or that one"is on automatic pilot." Most patients report a sense of emotional detachment or uninvolvement, or a sense of emotional numbing. Depersonalization differs from "derealization," which is a dissociative symptom in which people perceive the external world as unreal, dreamlike, or changing. The various ways that people experience depersonalization are related to their bodies or their sense of self.

Depersonalization is a common experience in the general adult population. However, when a patient's symptoms of depersonalization are severe enough to cause significant emotional distress, or interfere with normal functioning, the criteria of the DSM-IV-TR for "depersonalization disorder" are met.

Description

A person suffering from depersonalization disorder experiences subjective symptoms of unreality that make him or her uneasy and anxious. "Subjective" is a word that refers to the thoughts and perceptions inside an individual's mind, as distinct from the objects of those thoughts and perceptions outside the mind. Because depersonalization is a subjective experience, many people who have chronic or recurrent episodes of depersonalization are afraid others will not understand if they try to describe what they are feeling, or will think they are "crazy." As a result, depersonalization disorder may be underdiagnosed because the symptom of depersonalization is underreported.

Causes

Depersonalization disorder, like the dissociative disorders in general, has been regarded as the result of severe abuse in childhood. This can be of a physical, emotional, and/or sexual nature.

Findings in 2002 indicate that emotional abuse in particular is a strong predictor of depersonalization disorder in adult life, as well as of depersonalization as a symptom in other mental disorders. Analysis of one study of 49 patients diagnosed with depersonalization disorder indicated much higher scores than the control subjects for the total amount of emotional abuse endured and for the maximum severity of this type of abuse. The researchers concluded that emotional abuse has been relatively neglected by psychiatrists compared to other forms of childhood trauma.

It is thought that abuse in childhood or trauma in adult life may account for the distinctive cognitive (knowledge-related) profile of patients with depersonalization disorder. These patients have significant difficulties focusing their attention, with spatial reasoning, and with short-term visual and verbal memory. However, they have intact reality testing. (Reality testing refers to a person's ability to distinguish between their internal experiences and the objective reality of persons and objects in the outside world.) Otherwise stated, a patient with depersonalization disorder may experience his/her body as unreal, but knows that "feelings aren't facts." The DSM-IV-TR specifies intact reality testing as a diagnostic criterion for depersonalization disorder.

The causes of depersonalization disorder are not completely understood. Recent advances in brain imaging and other forms of neurological testing, however, have confirmed that depersonalization disorder is a distinct diagnostic entity and should not be considered a subtype of PTSD.

No specific genes have been associated with susceptibility to depersonalization disorder as of early 2002. It is possible that a genetic factor will be identified in the future.

NEUROBIOLOGICAL. In the past few years, several features of depersonalization disorder have been traced to differences in brain functioning. A group of British researchers found that the emotional detachment that characterizes depersonalization is associated with a lower level of nerve cell responses in regions of the brain that are responsible for emotional feeling; an increased level of nerve cell responses was found in regions of the brain related to emotional regulation.

A group of American researchers concluded that patients with depersonalization disorder had different patterns of response to tests of the hypothalamic-pituitary-adrenal axis (HPA, the part of the brain involved in the "fight-or-flight" reaction to stress) than did patients with PTSD. Other tests by the same research team showed that patients with depersonalization disorder can be clearly distinguished from patients with major depression by tests of the functioning of the HPA axis.

Other neurobiological studies involving positron emission tomography (PET) measurements of glucose (sugar) metabolism in different areas of the brain found that patients with depersonalization disorder appear to have abnormal functioning of the sensory cortex. The sensory cortex is the part of the brain that governs the senses of sight, hearing, and perceptions of the location of one's body in space. These studies indicate that depersonalization is a symptom that involves differences in sensory perception and subjective experiences.

HISTORICAL. Depersonalization disorder may be a reflection of changes in people's sense of self or personal identity within Western cultures since the eighteenth century. Historians of psychiatry have noted that whereas some mental disorders, such as depression, have been reported since the beginnings of Western medicine, no instances of the dissociative disorders were recorded before the 1780s. It seems that changes in social institutions and the structure of the family since the mid-eighteenth century may have produced a psychological structure in Westerners that makes individuals increasingly vulnerable to self disorders—as they are now called. Experiences of the unreality of one's body or one's self, such as those that characterize depersonalization disorder, presuppose a certain notion of how the self is presumed to feel. The emphasis on individualism and detachment from one's family is a mark of adult maturity in contemporary Western societies that appears to be a contributing factor to the frequency of dissociative symptoms and disorders.