# 08 - Dissociative Disorders

# Dissociative Disorders

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Dissociative Disorders
Dissociative disorders are characterized by a disruption of and/or discontinuity in the
normal integration of consciousness, memory, identity, emotion, perception, body representation,
motor control, and behavior. Dissociative symptoms can potentially disrupt every area of
psychological functioning. This chapter includes dissociative identity disorder, dissociative
amnesia, depersonalization/derealization disorder, other specified dissociative disorder, and
unspecified dissociative disorder.
Dissociative disorders are frequently found in the aftermath of a wide variety of
psychologically traumatic experiences in children, adolescents, and adults. Throughout this
chapter, “traumatic experiences” refers to experiences that result in psychological sequelae, as
opposed to the physical impact that can cause traumatic brain injury. Therefore, in DSM-5, the
dissociative disorders are placed next to, but are not part of, the trauma- and stressor-related
disorders, reflecting the close relationship between these diagnostic classes. Both acute stress
disorder and posttraumatic stress disorder include dissociative symptoms, such as amnesia,
flashbacks, numbing, and depersonalization/derealization.
Dissociative symptoms are experienced as unbidden intrusions into awareness and behavior,
with accompanying losses of continuity in subjective experience (i.e., ‘‘positive’’ dissociative
symptoms such as division of identity, depersonalization, and derealization) and/or inability to
access information or to control mental functions that normally are readily amenable to access or
control (i.e., “negative” dissociative symptoms such as amnesia).
Across cultural contexts, risk factors for dissociative pathology include earlier onset of
trauma; neglect and sexual, physical, and emotional abuse by parents; cumulative early life
trauma and adversities; and repeated sustained trauma or torture associated with captivity (e.g.,
experienced by prisoners of war, victims of trafficking).
Depersonalization/derealization disorder is characterized by clinically significant persistent
or recurrent depersonalization (i.e., experiences of unreality or detachment from one’s mind, self,
or body) and/or derealization (i.e., experiences of unreality or detachment from one’s
surroundings). These alterations of experience are accompanied by intact reality testing. There is
no evidence of any distinction between predominantly depersonalization and predominantly
derealization symptoms. Individuals with this disorder can have depersonalization, derealization,
or both.
Dissociative amnesia is characterized by an inability to recall autobiographical information
that is inconsistent with normal forgetting. The amnesia may be localized (i.e., an event or period
of time), selective (i.e., a specific aspect of an event), or generalized (i.e., identity and life
history). In dissociative amnesia, memory deficits are primarily retrograde and often associated
with traumatic experiences (e.g., lack of recall of third grade when the individual was kidnapped
and held hostage). Although some individuals with amnesia promptly notice that they have gaps
or a sense of fragmentation in their remote memory, most individuals with dissociative disorders

F44.81
are initially unaware of their amnesia or minimize or rationalize the deficits. For them, awareness
of amnesia occurs when they realize that they do not recall their personal identity or when
circumstances make these individuals aware that important autobiographical information is
missing (e.g., when they discover
evidence or are told of past events that they cannot recall). Generalized dissociative amnesia
with loss of a major part or all of the individual’s life history and/or identity is rare.
Dissociative identity disorder is characterized by a) the presence of two or more distinct
personality states or an experience of possession and b) recurrent episodes of dissociative
amnesia. The fragmentation/division of identity may vary across cultural contexts (e.g.,
possession-form presentations) and with circumstance. Thus, individuals may experience
discontinuities in identity and memory that may not be immediately evident to others or are
obscured by attempts to hide dysfunction. Individuals with dissociative identity disorder
experience recurrent, inexplicable intrusions into their conscious functioning and sense of self
(e.g., voices; dissociated actions and speech; intrusive thoughts, emotions, and impulses);
alterations of sense of self (e.g., attitudes, preferences, and feeling like their body or actions are
not their own); odd changes of perception (e.g., depersonalization or derealization, such as
feeling detached, as if watching themself from outside their body); and intermittent functional
neurological symptoms. Stress often produces transient exacerbation of dissociative symptoms
that makes them more evident.
The residual category of other specified dissociative disorder includes presentations in which
symptoms characteristic of a dissociative disorder that cause clinically significant distress or
impairment predominate but do not meet the criteria for any of the specific dissociative
disorders. Examples 
include 
identity disturbances associated with less-than-marked
discontinuities in sense of self and agency, alterations of identity, or episodes of possession in
the absence of a history of episodes of dissociative amnesia; identity disturbance due to
prolonged and intensive coercive persuasion as may occur in sects/cults or terrorist
organizations; acute dissociative reactions to stressful events that last less than 1 month; and
dissociative trance, which is characterized by an acute narrowing or complete loss of awareness
of immediate surroundings that manifests as profound unresponsiveness or insensitivity to
environmental stimuli.
Dissociative Identity Disorder
Diagnostic Criteria
A. Disruption of identity characterized by two or more distinct personality states,
which may be described in some cultures as an experience of possession. The
disruption in identity involves marked discontinuity in sense of self and sense of
agency, accompanied by related alterations in affect, behavior, consciousness,
memory, perception, cognition, and/or sensory-motor functioning. These signs

and symptoms may be observed by others or reported by the individual.
B. Recurrent gaps in the recall of everyday events, important personal information,
and/or traumatic events that are inconsistent with ordinary forgetting.
C. The symptoms cause clinically significant distress or impairment in social,
occupational, or other important areas of functioning.
D. The disturbance is not a normal part of a broadly accepted cultural or religious
practice.
Note: In children, the symptoms are not better explained by imaginary playmates
or other fantasy play.
E. The symptoms are not attributable to the physiological effects of a substance
(e.g., blackouts or chaotic behavior during alcohol intoxication) or another
medical condition (e.g., complex partial seizures).
Diagnostic Features
The defining feature of dissociative identity disorder is the presence of two or more distinct
personality states or an experience of possession (Criterion A). The overtness or covertness of
these personality states varies as a function of psychological motivation, current level of stress,
cultural context, internal conflicts and dynamics, and emotional resilience, among other factors.
Sustained periods of identity confusion/alteration may occur when psychosocial pressures are
severe and/or prolonged. In those cases of dissociative identity disorder that present as the
individual being possessed by external identities (e.g., spirits, demons) (possession-form
dissociative identity disorder), and in a small proportion of non-possession-form cases,
manifestations of alternate identities are readily observable. Most individuals with nonpossession-form dissociative identity disorder do not overtly display, or only subtly display, their
discontinuity of identity, and only a minority present to clinical attention with discernible
alternation of identities. The elaboration of dissociative personality states with different names,
wardrobes, hairstyles, handwritings, accents, and so forth, occurs in only a minority of
individuals with the non-possession-form dissociative identity disorder and is not essential to
diagnosis. In those cases where alternate personality states cannot be directly observed, the
presence of distinct personality states can be identified by sudden alterations or discontinuities in
the individual’s sense of self and sense of agency (Criterion A), and recurrent dissociative
amnesias (Criterion B).
Criterion A symptoms are related to discontinuities of experience that can affect any aspect
of an individual’s functioning. Individuals with dissociative identity disorder may report the
feeling that they have suddenly become depersonalized observers of their own speech and
actions, which they may feel powerless to stop (i.e., impaired sense of self and impaired sense of
agency). These individuals may also report perceptions of voices (e.g., a child’s voice, voices
commenting on the individual’s thoughts or behavior, persecutory voices and command
hallucinations). In some cases, hearing voices is specifically denied, but the individual reports
multiple, perplexing, independent thought streams over which the individual experiences no
control. Individuals with dissociative identity disorder may report hallucinations in all sensory

modalities: auditory, visual, tactile, olfactory, and gustatory.
Strong emotions, impulses, thoughts, and even speech or other actions may suddenly
materialize, without a sense of personal ownership or control (i.e., lack of sense of agency).
Conversely, thoughts and emotions may unexpectedly vanish, and speech and actions are
abruptly inhibited. These experiences are frequently reported as ego-dystonic and puzzling.
Attitudes, outlooks, and personal preferences (e.g., about food, activities, gender identity) may
suddenly shift. Individuals may report that their bodies feel different (e.g., like a small child, the
opposite gender, different ages simultaneously). Alterations in sense of self and agency may be
accompanied by a feeling that attitudes, emotions, and behaviors—even the individual’s own
body—are “not mine” or are “not under my control.” Although most Criterion A symptoms are
subjective, these sudden discontinuities in speech, affect, and behavior may be witnessed by
family, friends, or the clinician.
In most individuals with dissociative identity disorder, switching/shifting of states is subtle
and may occur with only subtle changes in overt presentation. State switching may be more overt
in the possession form of dissociative identity disorder. In general, the individual with
dissociative identity disorder experiences himself or herself as multiple, simultaneously
overlapping and interfering states.
Dissociative amnesia (Criterion B) manifests in several major domains: 1) gaps in any aspect
of autobiographical memory (e.g., important life events like getting married or giving birth, lack
of recall of all school experiences before high school); 2) lapses in memory of recent events or
well-learned skills (e.g., how to do one’s job, use a computer, cook or drive); and 3) discovery of
possessions that the individual has no recollection of ever owning (e.g., clothing, weapons, tools,
writings or drawings that he or she must have created).
Dissociative fugues, with amnesia for travel, are common. Individuals may report suddenly
finding themselves in another city, at work, or even at home: in the closet, under the bed, or
running out of the house. Amnesia in individuals with dissociative identity disorder is not limited
to stressful or traumatic events; it can involve everyday events as well. Individuals may report
major gaps in ongoing memory (e.g., experiencing “time loss,” “blackouts,” or “coming to” in
the midst of doing something). Dissociative amnesia may be apparent to others (e.g., the
individual does not recall something others witnessed that he or she did or said, cannot remember
his or her own name, or may fail to recognize spouse, children, or close friends). Minimization or
rationalization of amnesia is common.
Possession-form identities in dissociative identity disorder typically manifest behaviorally as
if a “spirit,” supernatural being, or outside person has taken control, with the individual speaking
or acting in a distinctly different manner. For example, an individual’s behavior may give the
appearance that her identity has been replaced by the “ghost” of a girl who died by suicide in the
same community years before, speaking and acting as though she were still alive. The identities
that arise during possession-form dissociative identity disorder present recurrently, are unwanted
and involuntary, and cause clinically significant distress or impairment (Criterion C). However,
the majority of possession states that occur around the world are usually part of a broadly
accepted cultural or religious practice and therefore do not meet criteria for dissociative identity
disorder (Criterion D).

Associated Features
Individuals with dissociative identity disorder typically present with comorbid depression,
anxiety, substance abuse, self-injury, or another common symptom. Nonepileptic seizures and
other functional neurological symptoms are prominent in some presentations of dissociative
identity disorder, especially in some non-Western settings. Some individuals, especially in
Western settings, may present with apparently refractory neurological symptoms, such as
headaches, seizures, or symptoms suggestive of multiple sclerosis.
Individuals with dissociative identity disorder often conceal, or are not fully aware of,
disruptions in consciousness, amnesia, or other dissociative symptoms. Many individuals with
dissociative identity disorder report dissociative flashbacks during which they experience a
sensory reliving of a previous event as though it were occurring in the present, often with a
change of identity, a partial or complete loss of contact with or disorientation to current reality
during the flashback, and a subsequent amnesia for the content of the flashback. Individuals with
the disorder typically report multiple types of interpersonal maltreatment during childhood and
adulthood. Other overwhelming early life events, such as multiple long, painful, early-life
medical procedures, also may be reported. Nonsuicidal self-injury is frequent. On standardized
measures, these individuals report higher levels of hypnotizability and dissociative symptoms
compared with other clinical groups and healthy control subjects. Some individuals experience
transient psychotic phenomena or episodes.
Among personality features, avoidant personality features most often rate highest in
individuals with dissociative identity disorder, and some individuals with dissociative identity
disorder are so avoidant that they prefer to be alone. When decompensated, some individuals
with dissociative identity disorder display features of borderline personality disorder (i.e., selfdestructive high-risk behaviors, and mood instability). Many individuals with dissociative
identity disorder display attachment problems but typically do not exhibit frantic activity to
avoid being abandoned. Some have stable long-term relationships, albeit frequently
dysfunctional and/or abusive ones, from which they may have difficulty extricating themselves.
Obsessional personality features are common in dissociative identity disorder, more so than
histrionic personality features. A subgroup of
individuals with dissociative identity disorder have narcissistic and/or antisocial personality
features.
Prevalence
The 12-month prevalence of dissociative identity disorder among adults in a small U.S.
community study was 1.5%. Lifetime prevalence of dissociative identity disorder was 1.1% in a
representative sample of community-based women in mid-eastern Turkey.
Development and Course
The disorder may first manifest at almost any age from early childhood to late life. Children
usually do not present with identity shifting, instead presenting primarily with independently
acting, imaginary companions, or as personified “mood” states (Criterion A phenomena).

Environmental.
Genetic and physiological.
Course modifiers.
Dissociation in children may generate problems with memory, concentration, and attachment,
and may be associated with traumatic play. In adolescents, dissociative identity disorder
commonly comes to clinical attention because of externalizing symptoms, suicidal/selfdestructive behavior, or rapid behavioral shifts often ascribed to other disorders such as
attention-deficit/hyperactivity disorder or childhood bipolar disorder. Some children with
dissociative identity disorder can also be quite aggressive and irritable. Older individuals with
dissociative identity disorder may present with symptoms that appear to be late-life mood
disorders, obsessive-compulsive disorder, paranoia, psychotic mood disorders, or even cognitive
disorders attributable to dissociative amnesia.
Overt identity alteration/confusion may be triggered by many factors, such as later traumatic
experiences (e.g., sexual assault), or even seemingly inconsequential stressors, like a minor
motor vehicle accident. The experience of other major or cumulative life stressors may also
worsen symptoms, including life events such as the individual’s children reaching the same age
at which the individual was significantly abused or traumatized. The death of, or the onset of a
fatal illness in, the individual’s abuser(s) is another example of an event that may worsen
symptoms. Individuals with dissociative identity disorder are at high risk for adult interpersonal
trauma such as rape, intimate partner violence, and sexual exploitation, including ongoing
incestuous abuse into adulthood, as well as adult trafficking.
Risk and Prognostic Factors
In the context of family and attachment pathology, early life trauma (e.g., neglect
and physical, sexual, and emotional abuse, usually before ages 5–6 years) represents a risk factor
for dissociative identity disorder. In studies from diverse geographic regions, about 90% of the
individuals with the disorder report multiple types of early neglect and childhood abuse, often
extending into late adolescence. Some individuals report that maltreatment primarily occurred
outside the family, in school, church, and/or neighborhoods, including being bullied severely.
Other forms of repeated early-life traumatic experiences include multiple, painful childhood
medical and surgical procedures; war; terrorism; or being trafficked beginning in childhood.
Onset has also been described after prolonged and often transgenerational exposure to
dysfunctional family dynamics (e.g., overcontrolling parenting, insecure attachment, emotional
abuse) in the absence of clear neglect or sexual or physical abuse.
Twin studies suggest that genetics account for around 45%–50% of the
interindividual variance in dissociative symptoms, with nonshared, stressful, and traumatic
environmental experiences accounting for most of the additional variance. Several brain regions
have been implicated in the pathophysiology of dissociative identity disorder, including the
orbitofrontal cortex, hippocampus, parahippocampal gyrus, and amygdala.
Ongoing sexual, physical, and emotional trauma often leads to significant
difficulties in later functioning. Poorer outcome in adults is commonly related to severe
psychosocial stressors, revictimization, ongoing sexual or physical abuse or exploitation,
intimate partner violence, refractory substance use, eating disorders, severe medical illness,
enmeshment with the individual’s abusive family of origin, or ongoing involvement in criminal

subgroups. Poorer functioning may also be related to perpetration of child maltreatment or
intimate partner violence by individuals with dissociative identity disorder.
Culture-Related Diagnostic Issues
Many features of dissociative identity disorder can be influenced by the individual’s
sociocultural background. In settings where possession symptoms are common (e.g., rural areas
in low- and middle-income countries, among certain religious groups in the United States and
Europe), all or some of the fragmented identities may take the form of possessing spirits, deities,
demons, animals, or mythical figures. Acculturation or prolonged intercultural contact may shape
the presentation of the other identities (e.g., identities in India may speak English exclusively and
wear Western clothes). Possession-form dissociative identity disorder can be distinguished from
culturally accepted possession states in that the former is involuntary, distressing, and
uncontrollable; involves conflict between the individual and his or her surrounding family,
social, or work milieu; and is manifested at times and in places that violate cultural or religious
norms. Combined dissociative-psychosis episodes may be more common in cultural contexts
with marked communal violence or oppression and limited opportunity for redress.
Sex- and Gender-Related Diagnostic Issues
Women with dissociative identity disorder predominate in adult clinical settings but not in
child/adolescent clinical settings or in general population studies. Few differences in symptom
profiles, clinical history, and childhood trauma history have been found in comparisons between
men and women with dissociative identity disorder, except that women may have higher rates of
somatization.
Association With Suicidal Thoughts or Behavior
Suicidal behavior is frequent. Over 70% of outpatients with dissociative identity disorder have
attempted suicide; multiple attempts are common, and other self-injurious and high-risk
behaviors are highly prevalent. Individuals with dissociative identity disorder have multiple
interacting risk factors for self-destructive and/or suicidal behavior. These include cumulative,
severe early- and later-life trauma; high rates of comorbid posttraumatic stress disorder (PTSD),
depressive disorders, and substance use disorders; and personality disorder features. Dissociation
itself is an independent risk factor for multiple suicide attempts. Greater severity of dissociative
symptom scores is associated with a higher frequency of suicide attempts and nonsuicidal selfinjury among individuals with dissociative disorders.
Functional Consequences of Dissociative Identity Disorder
Some children and adolescents with dissociative identity disorder may function poorly in school
and in relationships. Others do well in school, experiencing it as a respite. In adults impairment
varies widely, from apparently minimal (e.g., in high-functioning professionals) to profound. The
symptoms of higher-functioning individuals may impair their relational, marital, family, and
parenting functions more than their occupational and professional life, although the latter also
may be affected. Many impaired individuals show improvement in occupational and personal
functioning over time, while some individuals with dissociative

Dissociative amnesia.
Depersonalization/derealization disorder.
Major depressive disorder.
Bipolar disorders.
Posttraumatic stress disorder.
identity disorder may be impaired in most activities of living and function at the level of chronic
and persistent mental illness.
Differential Diagnosis
Both dissociative identity disorder and dissociative amnesia are
characterized by gaps in the recall of everyday events, important personal information, or
traumatic events that are inconsistent with ordinary forgetting. Dissociative identity disorder is
distinguished from dissociative amnesia by the additional presence of identity disruption
characterized by two or more distinct personality states.
The essential feature of depersonalization/derealization
disorder is persistent or recurrent episodes of depersonalization, derealization, or both.
Individuals with depersonalization/derealization disorder do not experience the presence of
personality/identity states with alterations of self and agency, nor do they typically report
dissociative amnesia.
Most individuals with dissociative identity disorder endorse a lifelong
negative posttraumatic emotional state, often with childhood onset, and their symptoms may
appear to meet the criteria for a major depressive episode. Moreover, posttraumatic reactivity to
times of year when trauma occurred (anniversary reactions), primarily manifesting with more
despondency, distress, and suicidal ideation, may also appear to be major depressive disorder,
with seasonal pattern. However, individuals with major depressive disorder or persistent
depressive disorder do not experience dissociative fluctuations in self and agency and
dissociative amnesia. It is important to assess if all or most identity states are experiencing the
adverse mood state, since mood disorder symptoms may fluctuate because they are experienced
in some identity states, but not others.
Dissociative identity disorder is commonly misdiagnosed as bipolar disorder,
typically bipolar II disorder, with mixed features. The relatively rapid shifts in behavioral state in
individuals with dissociative identity disorder—usually within minutes or hours—are atypical for
even the most rapid-cycling individuals with bipolar disorders. These state alterations are due to
rapidly shifting dissociative states and/or fluctuating posttraumatic intrusions. Sometimes these
shifts are accompanied by rapid changes in levels of activation, but these usually last minutes to
hours, not days, and are associated with activation of specific identity states. Elevated or
depressed mood may be experienced as loculated in specific identities, through
overlap/interference phenomena. Usually, the individual with dissociative identity disorder does
not have a classic bipolar sleep disturbance (e.g., reduced need for sleep), instead suffering from
chronic, severe nightmares and nocturnal flashbacks that interrupt sleep.
A majority of individuals with dissociative identity disorder will
have symptoms that meet diagnostic criteria for comorbid PTSD. Dissociative symptoms
characteristic of dissociative identity disorder should be differentiated from the dissociative
amnesia, dissociative flashbacks, and depersonalization/derealization characteristic of acute
stress disorder, PTSD, or the dissociative subtype of PTSD. Dissociative amnesia in PTSD
typically manifests only for specific traumatic events or aspects of traumatic events, as opposed

Schizophrenia and other psychotic disorders.
Substance/medication-induced disorders.
Personality disorders.
to the chronic, complex dissociative amnesia characteristic of dissociative identity disorder.
Depersonalization/derealization symptoms in the dissociative subtype of PTSD are related to
specific posttraumatic reminders. Depersonalization/derealization symptoms in dissociative
identity disorder may occur not only in response to posttraumatic reminders, but also in an
ongoing fashion in daily life, including in response to stressful interpersonal interactions and
when there is overlap/interference between states.
Individuals with dissociative identity disorder may
experience symptoms that can superficially appear similar to those of psychotic
disorders. These include auditory hallucinations and symptoms characteristic of intrusions of
personality states into the individual’s awareness; these symptoms can seemingly resemble some
of the Schneiderian first-rank symptoms formerly considered indicative of schizophrenia (e.g.,
thought broadcasting, thought insertion, thought withdrawal, hearing voices keeping up a
running commentary about the individual). For example, hearing different personality states
discussing the individual can resemble auditory hallucinations of voices arguing in
schizophrenia. The individual with dissociative identity disorder may also experience the
thoughts or emotions of an intruding personality state, which can resemble thought insertion in
schizophrenia, as well as experience the sudden disappearance of these thoughts or emotions,
which can resemble thought withdrawal. Such experiences in an individual with schizophrenia
are usually accompanied by delusional beliefs about the cause of those symptoms (i.e., thoughts
being inserted by an outside force), whereas individuals with dissociative identity disorder
typically experience these symptoms as ego-alien and frightening. Individuals with dissociative
identity disorder may also report a range of visual, tactile, olfactory, gustatory, and somatic
hallucinations, which are usually related to autohypnotic, posttraumatic, and dissociative factors,
such as partial flashbacks, in contrast to individuals with schizophrenia, whose hallucinations are
primarily auditory and less commonly visual. Dissociative identity disorder and psychotic
disorders are therefore distinguished by symptoms characteristic of one of these conditions and
not the other (e.g., dissociative amnesia in dissociative identity disorder and not in psychotic
disorders). Finally, individuals with schizophrenia have low hypnotic capacity, whereas
individuals with dissociative identity disorder have the highest hypnotic capacity among all
clinical groups.
Individuals with dissociative identity disorder frequently
have a current or past history of substance use disorders. Symptoms associated with the
physiological effects of a substance (e.g., blackouts) should be distinguished from dissociative
amnesia in dissociative identity disorder if the substance in question is judged to be etiologically
related to the memory loss.
Individuals with dissociative identity disorder often present identities that
appear to encapsulate a variety of severe personality disorder features, suggesting a differential
diagnosis of personality disorder, especially of the borderline type. Importantly, however, the
individual’s longitudinal variability in personality style (attributable to inconsistency among
identities) differs from the pervasive and persistent dysfunction in affect management and
interpersonal relationships typical of those with personality disorders.

Posttraumatic amnesia due to brain injury.
Functional neurological symptom disorder (conversion disorder).
Factitious disorder and malingering.
Both dissociative identity disorder and traumatic brain
injury (TBI) are characterized by gaps in memory. Other characteristics of TBI include loss of
consciousness, disorientation and confusion, or, in more severe cases, neurological signs and
symptoms. A neurocognitive disorder due to TBI manifests either immediately after brain injury
occurs or immediately after the individual recovers consciousness after the injury, and persists
past the acute postinjury period. The cognitive presentation of a neurocognitive disorder
following TBI is variable and includes difficulties in the domains of complex attention, executive
function, and learning and memory, as well as slowed speed of information processing and
disturbances in social cognition. While depersonalization is not uncommon following TBI, the
additional neurocognitive features noted above help distinguish it from dissociative amnesia that
is part of dissociative identity disorder. Moreover, dissociative amnesia occurring in the context
of dissociative identity disorder is accompanied by a marked discontinuity in sense of self and
sense of agency, which are not features of TBI.
Functional neurological symptom
disorder may be distinguished from dissociative identity disorder by the absence of identity
alteration characterized by two or more distinct personality states or an
experience of possession. Dissociative amnesia in functional neurological symptom disorder is
more limited and circumscribed (e.g., amnesia for a nonepileptic seizure).
Individuals who feign dissociative identity disorder usually do
not report the subtle symptoms of intrusion characteristic of the disorder; instead they tend to
overreport media-based symptoms of the disorder, such as dramatic dissociative amnesia and
melodramatic switching behaviors, while underreporting less-publicized comorbid symptoms,
such as depression. Individuals who feign dissociative identity disorder tend to be relatively
undisturbed by or may even seem to enjoy “having” the disorder, or may ask clinicians to “find”
traumatic memories. In contrast, most individuals with genuine dissociative identity disorder are
ashamed of and overwhelmed by their symptoms, deny the diagnosis, underreport their
symptoms, and display minimization and avoidance of their trauma history.
Individuals who feign the symptoms of dissociative identity disorder usually create limited,
stereotyped alternate identities, with feigned amnesia related only to the events for which gain is
sought, with apparent switching behaviors and amnesia only displayed while being observed.
They may present an “all-good” identity and an “all-bad” identity in hopes of gaining
exculpation for a crime.
Comorbidity
Disorders that are comorbid with dissociative identity disorder include PTSD, depressive
disorders, substance-related disorders, feeding and eating disorders, obsessive-compulsive
disorder, antisocial personality disorder, and other specified personality disorder with avoidant,
obsessive-compulsive, or borderline personality traits. The most common forms of functional
neurological symptom disorder include nonepileptic seizures, gait disturbances, and paralyses.
Most commonly, nonepileptic seizures resemble grand mal seizures or complex partial seizures
with temporal lobe foci; others may mimic absence or partial seizures.

F44.0
Dissociative Amnesia
Diagnostic Criteria
A. An inability to recall important autobiographical information, usually of a
traumatic or stressful nature, that is inconsistent with ordinary forgetting.
Note: Dissociative amnesia most often consists of localized or selective amnesia
for a specific event or events; or generalized amnesia for identity and life history.
B. The symptoms cause clinically significant distress or impairment in social,
occupational, or other important areas of functioning.
C. The disturbance is not attributable to the physiological effects of a substance
(e.g., alcohol or other drug of abuse, a medication) or a neurological or other
medical condition (e.g., partial complex seizures, transient global amnesia,
sequelae of a closed head injury/traumatic brain injury, other neurological
condition).
D. The disturbance is not better explained by dissociative identity disorder,
posttraumatic stress disorder, acute stress disorder, somatic symptom disorder,
or major or mild neurocognitive disorder.
Coding note: The code for dissociative amnesia without dissociative fugue is F44.0.
The code for dissociative amnesia with dissociative fugue is F44.1.
Specify if:
F44.1 With dissociative fugue: Apparently purposeful travel or bewildered
wandering that is associated with amnesia for identity or for other important
autobiographical information.
Specifiers
The specifier “with dissociative fugue” applies when dissociative amnesia occurs in the context
of a dissociative fugue, which is characterized by apparently purposeful travel or bewildered
wandering that is associated with amnesia for identity or other important autobiographical
information.
Diagnostic Features
The defining characteristic of dissociative amnesia is an inability to recall important
autobiographical information that 1) should be successfully stored in memory and 2) ordinarily
would be freely recollected (Criterion A). Dissociative amnesia is conceptualized as a potentially
reversible memory retrieval deficit. In this way, among others, it differs from the amnesias
attributable to neurobiological damage or toxicity that impair memory storage or retrieval.
A variety of types of dissociative amnesia may manifest. In general, the memory deficit in

dissociative amnesia is retrograde and, except in rare cases, is not associated with ongoing
amnesia for contemporary life events. Retrospective memory impairments include not only lost
memories of traumatic experiences but also lost memories of everyday life during which no
trauma occurred. Most commonly, individuals with dissociative amnesia report localized
amnesia—a failure to recall events during a circumscribed period of time; and/or selective
amnesia—the individual can recall some, but not all, of the events during a circumscribed period
of time. In systematized amnesia the individual fails to recall a specific category of important
information (e.g., fragmentary recall of home growing up, but continuous memory for school; no
recall of a violent older sibling; lack of recall of a specific room in the individual’s childhood
home). Individuals rarely overtly complain of symptoms of these forms of dissociative amnesia
and attempt to minimize and rationalize the memory loss.
Generalized dissociative amnesia involves a complete loss of memory for most or all of the
individual’s life history. Individuals with generalized amnesia may forget personal identity (e.g.,
a woman loses memory of her entire life history after giving in to repeated pressure from a close
friend to engage in a sexual relationship), lose previous knowledge about the world (e.g., recent
political events, how to use current technology), and less commonly lack access to well-learned
skills (e.g., what contact lenses are and how to put them in). Generalized dissociative amnesia
has an acute onset; the perplexity, disorientation, and purposeless wandering of individuals with
generalized amnesia usually bring them to the attention of the police or psychiatric emergency
services. Dissociative fugue is commonly associated with generalized dissociative amnesia and
can be indicated by using the “with dissociative fugue” specifier. Generalized dissociative
amnesia may be more common among combat veterans, sexual assault victims, and individuals
experiencing extreme emotional stress or conflict. In continuous amnesia (i.e., anterograde
dissociative amnesia), an individual forgets each new event as it occurs.
Individuals with dissociative amnesia are frequently unaware (or only partially aware) of
their memory problems. They may recall some traumatic events, or parts of traumatic events, but
not others of the same type. Many, especially those with localized amnesia, minimize the
importance of their memory loss and may become uncomfortable when prompted to address it.
Associated Features
Many individuals with dissociative amnesia are chronically impaired in their ability to form and
sustain satisfactory relationships. Histories of trauma, especially child abuse, and victimization
are common. Some individuals with dissociative amnesia report dissociative flashbacks (i.e.,
behavioral reexperiencing of traumatic events). Many have a history of
nonsuicidal self-injury, suicide attempts, and other high-risk behaviors. Depressive and
functional neurological symptoms are common, as are depersonalization, auto-hypnotic
symptoms, and high hypnotizability. Sexual dysfunctions are common. Mild traumatic brain
injury (TBI) may precede dissociative amnesia.
Prevalence
The 12-month prevalence for dissociative amnesia among adults in a small U.S. community

Environmental.
study was 1.8%.
Development and Course
Dissociative amnesia has been observed in young children, adolescents, adults, and geriatric
populations. Amnesia in children younger than 12 may be the most difficult to evaluate because
they often have difficulty understanding questions about amnesia, and interviewers may find it
difficult to formulate child-friendly questions about memory and amnesia, especially in younger
children. Observations of apparent dissociative amnesia are often difficult to differentiate from
inattention, absorption, daydreaming, anxiety, oppositional behavior, and learning disorders.
Reports from several different sources (e.g., teacher, therapist, case worker) may be needed to
diagnose amnesia in children. Some traumatized adolescents with dissociative amnesia are less
likely to come to clinical attention because of lower levels of posttraumatic stress disorder
(PTSD) intrusive symptoms and less externalizing behavior. Dissociative fugue behavior in
children and adolescents may be limited by the child’s life space (e.g., a child in a fugue “coming
to” after bicycling to an unfamiliar neighborhood, a teenager finding herself having taken public
transportation to a nearby town).
Onset of generalized amnesia is usually sudden. Individuals may experience multiple
episodes of this type of dissociative amnesia. A single episode may predispose to future
episodes. In between episodes of amnesia, the individual may or may not appear to be acutely
symptomatic. Some episodes of acute generalized amnesia resolve rapidly (e.g., when the
individual is removed from combat or some other stressful situation, and/or is brought to clinical
attention). A substantial subgroup of individuals develop highly impairing, debilitating, chronic
autobiographical memory deficits, such that even “relearning” their life history does not
ameliorate the memory loss.
Removal from the traumatic circumstances generating acute, generalized dissociative
amnesia (e.g., combat) may bring about a rapid return of memory. The memory loss of
individuals with dissociative fugue may be particularly refractory. Later life trauma, life stresses,
or losses may precede breakdown of long-standing autobiographical memory deficits related to
childhood or adult trauma, with the onset of acute PTSD, mood disorders, substance abuse, and
dangerousness to self or others, among other symptoms.
Risk and Prognostic Factors
Severe, acute, or chronic traumatization is the main risk factor for dissociative
amnesia. Cumulative early life trauma and adversities, especially physical and sexual abuse, are
the major risk factors for dissociative amnesia for childhood and adolescence. More severe
sexual abuse, multiple episodes of childhood sexual abuse, and sexual abuse by a relative,
especially with betrayal by a close attachment figure, may increase the extent of childhood
autobiographical memory disturbances. Individuals with dissociative amnesia may deny recall of
specific childhood traumas (e.g., sexual assault), even those documented in medical or social
service reports, although the individual can recall other similar traumatic events, both before and
after the amnestic event. Severe cumulative adult trauma (e.g., repeated combat, trafficking,
prisoner-of-war or concentration camp

Genetic and physiological.
experiences) also may result in extensive localized, selective, and/or systematized dissociative
amnesia. Generalized dissociative amnesia may be more common among individuals who have
recently experienced extreme acute traumas (e.g., brutal military combat, rape, torture, often in
the context of inability to escape) and/or a prior history of major social dislocation, asylumseeking, or refugee status. Others develop generalized amnesia in the context of profound
psychological conflict from which the individual also feels unable to escape. Virtually all
individuals who develop generalized dissociative amnesia in the context of psychological
conflict report past histories of severe early life and/or adult traumatization. Extreme acute
traumatic experiences also may engender major psychological conflicts (e.g., a woman develops
generalized amnesia after experiencing a brutal rape resulting in an unwanted pregnancy and
becomes suicidal; on assessment, she reveals that her religion views abortion as murder and
suicide as a major sin).
Quantitative genetic studies suggest that genetics account for about
50% of the interindividual variance in dissociative symptoms, with nonshared, stressful
environmental experiences accounting for most of the additional variance. Candidate gene
studies suggest a gene x environment interplay with earlier and more chronic childhood
traumatic experiences leading to significant increases in dissociative symptoms later in life.
Culture-Related Diagnostic Issues
In cultural contexts where possession is part of normative religious or spiritual practice,
dissociative amnesia and fugue may be interpreted as resulting from pathological possession. In
contexts or situations where individuals feel highly constrained by social circumstances or
cultural traditions, the precipitants of dissociative amnesia often do not involve frank trauma.
Instead, the amnesia may be preceded by severe psychological stresses or conflicts (e.g., marital
conflict, other family disturbances, attachment problems, or conflicts attributable to restriction or
oppression).
Association With Suicidal Thoughts or Behavior
Suicidal and other self-destructive behaviors are common in individuals with dissociative
amnesia. The psychological forces producing generalized amnesia may be extreme, and suicidal
thoughts, impulses, plans, and behavior are a risk when amnesia decreases. Case reports suggest
that suicidal behavior may be a particular risk when the amnesia remits suddenly and
overwhelms the individual with intolerable memories.
Functional Consequences of Dissociative Amnesia
Impairments in individuals with dissociative amnesia resulting from childhood/adolescent
traumatization range from limited to severe. Some of these individuals may be chronically
impaired in their ability to form and sustain satisfactory attachments. Some may become highly
successful in occupational functioning but often do so by compulsive overwork. Individuals with
acute generalized dissociative amnesia usually have impairment in all aspects of functioning. A
substantial subgroup of individuals with generalized amnesia develop a highly impairing, chronic
autobiographical memory deficit that even relearning their life history does not ameliorate. These
individuals experience a highly debilitated, chronic course with poor overall functioning in most

Dissociative identity disorder.
Posttraumatic stress disorder.
Neurocognitive disorders.
Substance-related disorders.
domains of life.
Differential Diagnosis
Recurrent episodes of dissociative amnesia may be attributable to
dissociative identity disorder. Individuals with dissociative amnesia may report depersonalization
and auto-hypnotic symptoms, as do individuals with dissociative
identity disorder. Individuals with dissociative identity disorder report pervasive discontinuities
in sense of self and agency, accompanied by many other dissociative symptoms. Amnesias in
dissociative identity disorder, in addition to retrospective autobiographical memory deficits,
include ongoing amnesia (“time loss”) for everyday events and interpersonal interactions;
finding unexplained possessions; perplexing major fluctuations in skills and knowledge; and
frequent, brief amnesic gaps during interpersonal interactions.
Some individuals with PTSD cannot recall part or all of a specific
traumatic event (e.g., a rape victim who cannot recall most events for the entire day of the rape).
When that amnesia extends to events beyond the immediate time of the trauma, a comorbid
diagnosis of dissociative amnesia may be warranted. Individuals with the dissociative subtype of
PTSD may also report dissociative amnesia in addition to depersonalization/derealization.
In major neurocognitive disorders, there is typically evidence of neural
tissue damage accompanied by a decline in cognitive function with deficits in attention,
executive function, learning and memory, language, and perceptual-motor and social cognition
that impair capacity for independent everyday activities. Memory loss for personal information is
usually embedded in cognitive, linguistic, affective, attentional, and behavioral disturbances.
Generally, awareness of personal identity is spared until late in the course of the neurocognitive
disorder. In neurocognitive disorders, retrograde amnesia is almost always accompanied by
anterograde amnesia. Anterograde dissociative amnesia can be confused with delirium. However,
medical, laboratory, toxicological, and neurological workups, including imaging studies, are
normal. Careful, repeated evaluations over time will show that as in other forms of dissociative
amnesia, there are no true neurocognitive deficits.
In the context of repeated intoxication with alcohol or other
substances/medications, there may be episodes of “blackouts” or periods for which the individual
has no memory, or partial memory (“grayouts”). To aid in distinguishing these episodes from
dissociative amnesia, a longitudinal history should show that the amnestic episodes occur only in
the context of intoxication. However, the distinction may be difficult when the individual with
dissociative amnesia also misuses alcohol or other substances, particularly in the context of
stressful situations that may also exacerbate dissociative symptoms. This can be a more complex
differential diagnosis when the substance use begins in childhood or adolescence, generally in
the context of intrafamilial abuse, neglect, and substance-related disorders. Sequential
observation of these individuals after detoxification, along with carefully taken history, usually
can distinguish the memory loss attributable to long-standing substance use from dissociative
amnesia. Some individuals with comorbid dissociative amnesia and substance use disorders will
attempt to minimize their dissociative amnesia and attribute memory problems solely to the

Posttraumatic amnesia due to brain injury.
Seizure disorders.
Memory deficits associated with electroconvulsive therapy.
Catatonic stupor.
substance use. Prolonged use of alcohol or other substances may result in a substance-induced
neurocognitive disorder that may be associated with impaired cognitive function. However, in
this context the protracted history of substance use and the persistent deficits associated with the
neurocognitive disorder would serve to distinguish it from dissociative amnesia, where there is
typically no evidence of persistent impairment in intellectual functioning.
Amnesia may occur in the context of a TBI when there
has been an impact to the head or other mechanisms of rapid movement or displacement of the
brain within the skull. Other characteristics of TBI include loss of consciousness, disorientation
and confusion, or, in more severe cases, neurological signs and symptoms (e.g., abnormalities on
neuroimaging, a new onset of seizures or a marked worsening of a preexisting seizure disorder,
visual field cuts, anosmia). A neurocognitive disorder attributable to TBI must present either
immediately after brain injury occurs or immediately after the individual recovers consciousness
after the injury, and persist past the
acute postinjury period. The cognitive presentation of a neurocognitive disorder following TBI is
variable and includes difficulties in the domains of complex attention, executive function,
learning and memory, as well as slowed speed of information processing and disturbances in
social cognition. The patterns of memory deficits are typical of neurocognitive disorders. Mild
TBI may precede acute dissociative amnesia presentations, but the dissociative memory deficits
are out of proportion to the TBI head trauma and typically follow the dissociative, not the
neurocognitive, patterns.
Individuals with seizure disorders may exhibit complex behavior during
seizures or postictally with subsequent amnesia. Some individuals with a seizure disorder engage
in nonpurposive wandering that is limited to the period of seizure activity. Conversely, behavior
during a dissociative fugue is usually purposeful, complex, and goal-directed and may last for
days, weeks, or longer. Occasionally, individuals with a seizure disorder will report that some
autobiographical memories have been “wiped out” as the seizure disorder progresses. Such
memory loss is not associated with psychological trauma or adversities and appears to occur
randomly. In seizure disorders, serial electroencephalograms usually show abnormalities.
Telemetric electroencephalographic monitoring generally shows an association between the
episodes of amnesia and seizure activity. Dissociative and epileptic amnesias may coexist.
Memory deficits after electroconvulsive
therapy (ECT) most commonly occur for the day of ECT administration. More extensive
retrograde and even anterograde amnesia after ECT is usually unrelated to stressful or traumatic
life epochs, and generally remits after the ECT series concludes. ECT in severely depressed
individuals with dissociative disorders does not worsen dissociation, and memory access may
improve as depression remits.
Mutism in catatonic stupor may suggest dissociative amnesia, but failure of
recall is usually absent. Other catatonic symptoms (e.g., rigidity, posturing, negativism) are
usually present. Catatonic symptoms in children can be associated with trauma, abuse, and/or
deprivation. Unlike in dissociative amnesia, the pattern of memory loss in catatonia is only for
the catatonic episode.

Acute dissociative reactions to stressful events (other specified dissociative disorder).
Factitious disorder and malingering.
Memory changes with aging or mild neurocognitive disorder.
The 
acute
dissociative reactions to stressful events example of other specified dissociative disorder is
characterized by a combination of dissociative symptoms that occur together acutely in response
to stressful events and typically last less than 1 month. Amnestic episodes that occur as part of
these reactions are accompanied by other prominent dissociative symptoms, have a short
duration (hours or days), and tend to be circumscribed to limited periods or events in a person’s
life (micro-amnesias).
There is no test, battery of tests, or set of procedures that
invariably distinguishes dissociative amnesia from feigned amnesia. Feigned amnesia is more
common in individuals with 1) acute, florid dissociative amnesia; 2) financial, sexual, or legal
problems; 3) a wish to escape stressful circumstances; 4) a desire to seem to be a more
interesting patient; and/or 5) a plan to engage in litigation for “recovered memories.” However,
dissociative amnesia can be associated with those same circumstances and can coexist with
deliberate feigning. Many individuals who malinger amnesia confess spontaneously or when
confronted.
Memory 
decrements 
in 
mild
neurocognitive disorder differ from those of dissociative amnesia; in mild neurocognitive
disorder, memory changes manifest as difficulty in learning and retaining new information. This
is often measured in tests of verbal learning of word lists or a brief story with evaluation of
immediate and delayed recall. With normal cognitive aging, individuals may also have similar
weaknesses in immediate and delayed recall of new information,
although normal aging may also affect information processing speed and other complex
executive function tasks in addition to memory.
Comorbidity
As is common in individuals with a history of trauma, many comorbidities co-occur with
dissociative amnesia, particularly as dissociative amnesia begins to remit. A wide variety of
affective phenomena may surface, including dysphoria, grief, rage, shame, guilt, and
psychological conflict and turmoil. Individuals may engage in nonsuicidal self-injury and other
high-risk behaviors. These individuals may have symptoms that meet diagnostic criteria for
persistent depressive disorder, major depressive disorder, or subthreshold depression (other
specified depressive disorder). Many individuals with dissociative amnesia develop PTSD at
some point during their life, especially when the traumatic antecedents of their amnesia are
brought into conscious awareness. Many of these individuals may show symptoms of the
dissociative subtype of PTSD. Many individuals with dissociative amnesia have symptoms that
meet diagnostic criteria for a comorbid somatic symptom and related disorder (and vice versa),
particularly functional neurological symptom disorder (conversion disorder). Substance-related
and addictive disorders may be comorbid with dissociative amnesia, as well as feeding and
eating disorders and sexual dysfunctions. The most common comorbid personality disorder is
other specified personality disorder (with mixed personality disorder features), which often
includes avoidant, obsessive-compulsive, dependent, and borderline features.

F48.1
Depersonalization/Derealization Disorder
Diagnostic Criteria
A. The presence of persistent or recurrent experiences of depersonalization,
derealization, or both:
1. Depersonalization: Experiences of unreality, detachment, or being an
outside observer with respect to one’s thoughts, feelings, sensations, body, or
actions (e.g., perceptual alterations, distorted sense of time, unreal or absent
self, emotional and/or physical numbing).
2. Derealization: Experiences of unreality or detachment with respect to
surroundings (e.g., individuals or objects are experienced as unreal,
dreamlike, foggy, lifeless, or visually distorted).
B. During the depersonalization or derealization experiences, reality testing remains
intact.
C. The symptoms cause clinically significant distress or impairment in social,
occupational, or other important areas of functioning.
D. The disturbance is not attributable to the physiological effects of a substance
(e.g., a drug of abuse, medication) or another medical condition (e.g., seizures).
E. The disturbance is not better explained by another mental disorder, such as
schizophrenia, panic disorder, major depressive disorder, acute stress disorder,
posttraumatic stress disorder, or another dissociative disorder.
Diagnostic Features
The essential features of depersonalization/derealization disorder are persistent or recurrent
episodes of depersonalization, derealization, or both. Episodes of depersonalization are
characterized by a feeling of unreality or detachment from, or unfamiliarity with, the individual’s
whole self or from aspects of the self (Criterion A1). The individual may feel detached from his
or her entire being (e.g., “I am no one,” “I have no self”). He or she may
also feel subjectively detached from aspects of the self, including feelings (e.g.,
hypoemotionality: “I know I have feelings, but I don’t feel them”), thoughts (e.g., “My thoughts
don’t feel like my own,” “head filled with cotton”), whole body or body parts, or sensations (e.g.,
touch, proprioception, hunger, thirst, libido). There may also be a diminished sense of agency
(e.g., feeling robotic, like an automaton; lacking control of speech or movements). The
depersonalization experience can sometimes be one of a split self, with one part observing and
one participating, known as an “out-of-body experience” in its most extreme form. The unitary
symptom of “depersonalization” consists of several symptom factors: anomalous body
experiences (i.e., unreality of the self and perceptual alterations); emotional or physical numbing;

and temporal distortions with anomalous subjective recall.
Episodes of derealization are characterized by a feeling of unreality or detachment from, or
unfamiliarity with, the world, be it individuals, inanimate objects, or all surroundings (Criterion
A2). The individual may feel as if he or she were in a fog, dream, or bubble, or as if there were a
veil or a glass wall between the individual and the world around. Surroundings may be
experienced as artificial, colorless, or lifeless. Derealization is commonly accompanied by
subjective visual distortions, such as blurriness, heightened acuity, widened or narrowed visual
field, two-dimensionality or flatness, exaggerated three-dimensionality, or altered distance or
size of objects (i.e., macropsia or micropsia). Auditory distortions can also occur, whereby
voices or sounds are muted or heightened. In addition, Criterion C requires that the symptoms
cause clinically significant distress or impairment in social, occupational, or other important
areas of functioning, and Criteria D and E describe exclusionary diagnoses.
Associated Features
Individuals with depersonalization/derealization disorder may have difficulty describing their
symptoms and may think they are “crazy” or “going crazy.” Another common experience is the
fear of irreversible brain damage. A commonly associated symptom is a subjectively altered
sense of time (i.e., too fast or too slow), as well as a subjective difficulty in vividly recalling past
memories and owning them as personal and emotional. Vague somatic symptoms, such as head
fullness, tingling, or lightheadedness, are not uncommon. Individuals may experience extreme
rumination or obsessional preoccupation (e.g., constantly obsessing about whether they really
exist, or checking their perceptions to determine whether they appear real). Varying degrees of
anxiety and depression are also common associated features. Individuals with the disorder have
been found to have physiological hyporeactivity to emotional stimuli. Neural substrates of
interest include the hypothalamic-pituitary-adrenocortical axis, inferior parietal lobule, and
prefrontal cortical-limbic circuits.
Prevalence
Transient depersonalization/derealization symptoms lasting hours to days are common in the
general population. The 12-month prevalence of depersonalization/derealization disorder is
thought to be markedly less than for transient symptoms, although precise estimates for the
disorder are unavailable. In general, approximately one-half of all adults have experienced at
least one lifetime episode of depersonalization/derealization. However, symptomatology that
meets full criteria for depersonalization/derealization disorder is markedly less common than
transient symptoms. One-month prevalence in the United Kingdom is approximately 1%–2%.
Development and Course
The mean age at onset of depersonalization/derealization disorder is 16 years, although the
disorder can start in early or middle childhood; a minority cannot recall ever not having had the
symptoms. Less than 20% of individuals experience onset after age 20 years and only 5% after
age 25 years. Onset in the fourth decade of life or later is highly unusual.

Temperamental.
Environmental.
Onset can range from extremely sudden to gradual. Duration of depersonalization/derealization
disorder episodes can vary greatly, from brief (hours or days) to prolonged (weeks, months, or
years). Given the rarity of disorder onset after age 40 years, in such cases the individual should
be examined more closely for underlying medical conditions (e.g., brain lesions, seizure
disorders, sleep apnea). The course of the disorder is often persistent. About one-third of cases
involve discrete episodes; another third, continuous symptoms from the start; and still another
third, an initially episodic course that eventually becomes continuous.
While in some individuals the intensity of symptoms can wax and wane considerably, others
report an unwavering level of intensity that in extreme cases can be constantly present for years
or decades. Internal and external factors that affect symptom intensity vary between individuals,
yet some typical patterns are reported. Exacerbations can be triggered by stress, worsening mood
or anxiety symptoms, novel or overstimulating settings, and physical factors such as lighting or
lack of sleep.
Risk and Prognostic Factors
Individuals with depersonalization/derealization disorder are characterized by
harm-avoidant temperament, immature defenses, and both disconnection and overconnection
schemata. Immature defenses such as idealization/devaluation, projection, and acting out result
in denial of reality and poor adaptation. Cognitive disconnection schemata reflect defectiveness
and emotional inhibition and subsume themes of abuse, neglect, and deprivation. Overconnection
schemata involve impaired autonomy with themes of dependency, vulnerability, and
incompetence.
There is a clear association between the disorder and childhood interpersonal
traumas in a substantial portion of individuals, although this association is not as prevalent or as
extreme in the nature of the traumas as in other dissociative disorders, such as dissociative
identity disorder. In particular, emotional abuse and emotional neglect have been most strongly
and consistently associated with the disorder. Other stressors can include physical abuse;
witnessing domestic violence; growing up with a seriously impaired, mentally ill parent; or
unexpected death or suicide of a family member or close friend. Sexual abuse is a much less
common antecedent but can be encountered. The most common proximal precipitants of the
disorder are severe stress (interpersonal, financial, occupational), depression, anxiety
(particularly panic attacks), and illicit drug use. Symptoms may be specifically induced by
substances 
such 
as 
tetrahydrocannabinol, 
hallucinogens, 
ketamine, 
MDMA 
(3,4methylenedioxymethamphetamine; “ecstasy”), and salvia. Marijuana use may precipitate newonset panic attacks and depersonalization/derealization symptoms simultaneously.
Culture-Related Diagnostic Issues
Volitionally induced experiences of depersonalization/derealization can be a part of meditative
practices that are prevalent in many religious, spiritual, and cultural contexts and should not be
diagnosed as a disorder. However, there are individuals who initially induce these states
intentionally but over time lose control over them and may develop a fear and aversion for
related practices. Cultural frameworks may affect the level of distress or perceived severity
associated with uncontrolled depersonalization/derealization experiences by providing
explanations for them (e.g., spiritual/supernatural causes), which may alleviate individuals’ fears

Illness anxiety disorder.
Major depressive disorder.
Obsessive-compulsive disorder.
Other dissociative disorders.
Panic attacks.
that they are “losing their mind.”
Functional Consequences of Depersonalization/Derealization Disorder
Symptoms of depersonalization/derealization disorder are highly distressing and are associated
with major morbidity. The affectively flattened and robotic demeanor that these
individuals often demonstrate may appear incongruent with the extreme emotional pain reported
by those with the disorder. Impairment is often experienced in both interpersonal and
occupational spheres, largely as a result of the hypoemotionality with others, subjective difficulty
in focusing and retaining information, and a general sense of disconnectedness from life.
Differential Diagnosis
Although individuals with depersonalization/derealization disorder can
present with vague somatic complaints as well as fears of permanent brain damage, the diagnosis
of depersonalization/derealization disorder is characterized by the presence of a constellation of
typical depersonalization/derealization symptoms and the absence of other manifestations of
illness anxiety disorder.
Feelings of numbness, deadness, apathy, and being in a dream are not
uncommon in major depressive episodes. However, in depersonalization/derealization disorder,
such 
symptoms 
are 
associated 
with 
further 
symptoms 
of 
the 
disorder. 
If 
the
depersonalization/derealization clearly precedes the onset of a major depressive episode or
clearly continues after its resolution, the diagnosis of depersonalization/derealization disorder
applies.
Some individuals with depersonalization/derealization disorder
can become obsessively preoccupied with their subjective experience or develop rituals checking
on the status of their symptoms. However, other symptoms of obsessive-compulsive disorder
unrelated to depersonalization/derealization are not present.
In order to diagnose depersonalization/derealization disorder, the
symptoms should not occur in the context of another dissociative disorder, such as dissociative
identity disorder. Differentiation from dissociative amnesia and functional neurological symptom
disorder (conversion disorder) is simpler, as the symptoms of these disorders do not overlap with
those of depersonalization/derealization disorder.
Depersonalization/derealization is one of the symptoms of panic attacks,
increasingly 
common 
as 
panic 
attack 
severity 
increases. 
Therefore,
depersonalization/derealization disorder should not be diagnosed when the symptoms occur only
during panic attacks that are part of panic disorder, social anxiety disorder, or specific phobia. In
addition, it is not uncommon for depersonalization/derealization symptoms to first begin in the
context of new-onset panic attacks or as panic disorder progresses and worsens. In such
presentations, the diagnosis of depersonalization/derealization disorder can be made if 1) the
depersonalization/derealization component of the presentation is very prominent from the start,
clearly exceeding in duration and intensity the occurrence of actual panic attacks; or 2) the

Psychotic disorders.
Substance/medication-induced disorders.
Traumatic brain injury.
Dissociative symptoms due to another medical condition.
depersonalization/derealization continues after panic disorder has remitted or has been
successfully treated.
The presence of intact reality testing specifically regarding the
depersonalization/derealization 
symptoms 
is 
essential 
to 
differentiating
depersonalization/derealization disorder from psychotic disorders. Rarely, positive-symptom
schizophrenia can pose a diagnostic challenge when nihilistic delusions are present. For example,
an individual may complain that he or she is dead or the world is not real; this could be either a
subjective experience that the individual knows is not true or a delusional conviction.
Depersonalization/derealization 
associated 
with 
the
physiological effects of substances during acute intoxication or withdrawal is not diagnosed as
depersonalization/derealization disorder. The most common precipitating substances are the
illicit drugs marijuana, hallucinogens, ketamine, ecstasy, and salvia. In
about 15% of all cases of depersonalization/derealization disorder, the symptoms are precipitated
by ingestion of such substances. If the symptoms persist for some time in the absence of any
further substance or medication use, the diagnosis of depersonalization/derealization disorder
applies. This diagnosis is usually easy to establish since the vast majority of individuals with this
presentation become highly phobic and aversive to the triggering substance and do not use it
again.
Depersonalization/derealization symptoms are typical in traumatic brain
injury (TBI) but are distinguished from depersonalization/derealization disorder by onset of
symptoms following TBI and the lack of other symptoms of depersonalization/derealization
disorder.
Features such as onset after age 40 years or
the presence of atypical symptoms and course in any individual suggest the possibility of an
underlying medical condition. In cases with dissociative symptoms, it is essential to conduct a
thorough medical and neurological evaluation, which may include standard laboratory studies,
viral titers, an electroencephalogram, vestibular testing, visual testing, sleep studies, and/or brain
imaging. When the suspicion of an underlying seizure disorder proves difficult to confirm, an
ambulatory electroencephalogram may be indicated; although temporal lobe epilepsy is most
commonly implicated, parietal and frontal lobe epilepsy may also be associated.
Comorbidity
In a convenience sample of adults recruited for a number of depersonalization research studies,
lifetime comorbidities were high for unipolar depressive disorder and for any anxiety disorder,
with a significant proportion of the sample having both disorders. Comorbidity with
posttraumatic stress disorder was low. The three most commonly co-occurring personality
disorders were avoidant, borderline, and obsessive-compulsive.
Other Specified Dissociative Disorder

F44.89
This category applies to presentations in which symptoms characteristic of a
dissociative disorder that cause clinically significant distress or impairment in social,
occupational, or other important areas of functioning predominate but do not meet
the full criteria for any of the disorders in the dissociative disorders diagnostic class.
The other specified dissociative disorder category is used in situations in which the
clinician chooses to communicate the specific reason that the presentation does not
meet the criteria for any specific dissociative disorder. This is done by recording
“other specified dissociative disorder” followed by the specific reason (e.g.,
“dissociative trance”).
Examples of presentations that can be specified using the “other specified”
designation include the following:
1. Chronic and recurrent syndromes of mixed dissociative symptoms: This
category includes identity disturbance associated with less-than-marked
discontinuities in sense of self and agency, or alterations of identity or episodes
of possession in an individual who reports no dissociative amnesia.
2. Identity disturbance due to prolonged and intense coercive persuasion:
Individuals who have been subjected to intense coercive persuasion (e.g.,
brainwashing, thought reform, indoctrination while captive, torture, long-term
political imprisonment, recruitment by sects/cults or by terror organizations) may
present with prolonged changes in, or conscious questioning of, their identity.
3. Acute dissociative reactions to stressful events: This category is for acute,
transient conditions that typically last less than 1 month, and sometimes only a
few hours or days. These conditions are characterized by constriction of
consciousness; depersonalization; derealization; perceptual disturbances (e.g.,
time slowing, macropsia); microamnesias; transient stupor; and/or alterations in
sensory-motor functioning (e.g., analgesia, paralysis).
4. Dissociative trance: This condition is characterized by an acute narrowing or
complete loss of awareness of immediate surroundings that manifests as
profound unresponsiveness or insensitivity to environmental stimuli. The
unresponsiveness may be accompanied by minor stereotyped behaviors (e.g.,
finger movements) of which the individual is unaware and/or that he or she
cannot control, as well as transient paralysis or loss of consciousness. The
dissociative trance is not a normal part of a broadly accepted collective cultural
or religious practice.
Unspecified Dissociative Disorder

F44.9
This category applies to presentations in which symptoms characteristic of a
dissociative disorder that cause clinically significant distress or impairment in social,
occupational, or other important areas of functioning predominate but do not meet
the full criteria for any of the disorders in the dissociative disorders diagnostic class.
The unspecified dissociative disorder category is used in situations in which the
clinician chooses not to specify the reason that the criteria are not met for a specific
dissociative disorder and includes presentations for which there is insufficient
information to make a more specific diagnosis (e.g., in emergency room settings).