Download DISSOCIATIVE AMNESIA

DISSOCIATIVE AMNESIA
Homayoun Amini M.D.
Assis. Prof. of Psychiatry
Roozbeh Hospital
TUMS
INTRODUCTION
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Two main elements of dissociation :
1- they lack evidence of proximate
organic illness or pathophysiological
disturbance;
2 – the symptoms correspond to
ideas of the patient about how
parts of the body or mind
malfunction or fail to function;
DEFINITION
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Dissociative phenomena are limited to
amnesia
Key symptoms is the inability to recall
information, usually about stressfull or
traumatic events in person’s lives
There may be a loss of knowledge of
personal identity with preservation of other
information, often including complex learned
information or skills
DEFINITION
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It cannot be explained by ordinary
forgetfulness
There is no evidence of an underlying
brain disorder
Persons retain the capacity to learn new
information
SUBTYPES
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Localized: a circumscribed period of time
Selective: some, but not all, of the events
during a circumscribed period of time
Generalized: the person’s entire life
Continuous: events subsequent to a specific
time up to and including present
Systematized: certain categories of
information
EPIDEMIOLOGY
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Amnesia is the most common
dissociative symptoms
More often in women than in men
More often in young adults than in older
adults
Incidence increases during times of war
& natural disasters
EPIDEMIOLOGY
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In civilian cases, a history of head trauma or
brain damage is often present
The condition may be more frequent amongst
criminals or soldiers in distress
Tends to present to accident & emergency
departments and then to neurologists, but is
only seen secondarily in psychiatric
departments
ETIOLOGY
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Psychoanalytic approach:
emotional conflict, primary & secondary
gain
Hx of child abuse ??
Amnesia seems to be related to immediate
adult adjustment problems, rather than the
consequences of early child abuse
The theory of state-dependent learning
DIAGNOSIS
(DSM-IV-TR)
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A. The predominant disturbance is one or more episode of
inability to recall important personal information, usually of a
traumatic or stressful nature, that is too extensive to be
explained by ordinary forgetfulness.
B. The disturbance does not occur exclusively during the course
of dissociative identity disorder, dissociative fugue, PTSD, ASD,
or somatization disorder, and is not due to the direct
physiological effects of a substance (e.g., a drug of abuse, a
medication) or a neurological or other GMC (e.g., amnestic
disorder due to head trauma).
C. The symptoms cause clinically significant distress or
impairment in social, occupational, or other important areas of
functioning.
DIAGNOSIS
(ICD-10)
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G1. There must be no evidence of a physical disorder that can
explain the characteristic symptoms of this disorder (although
physical disorders may be present that give rise to other
symptoms).
G2. There are convincing associations in time between the onset
of symptoms of the disorder and stressful events, problems, or
needs.
G3. There must be amnesia, either partial or complete, for
recent events or problems that were or still are traumatic or
stressful.
G4. The amnesia is too extensive and persistent to be explained
by ordinary forgetfulness (although its depth and extent may
vary from one assessment to the next) or by intentional
simulation.
CLINICAL FEATURES
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Onset is often abrupt
Patients are usually aware that they have lost
their memories
Some patients are upset but others appear to
be unconcerned
Amnestic patients are usually alert before and
after the amnesia occurs
Depression and anxiety are common
predisposing factors
Distortions in time perception
DIFFERENTIAL DIAGNOSIS
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Clinicians should conduct:
- a medical history
- a physical examination
- a psychiatric history
- a MSE
- a laboratory workup
DIFFERENTIAL DIAGNOSIS…
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Is the amnesia a result of
an organic disease?
a psychiatric disorder?
a dissociative disorder?
DIFFERENTIAL DIAGNOSIS…
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Amnestic disorders:
- epileptic seizures: short duration, less
identity confusion, stereotypic
-head injury: brief retrograde amnesia +
longer anterograde amnes
- korsakoff’s syndrome: significant
anterograde amnesia + variable
rerograde amnesia, intact other cognitive
functions
DIFFERENTIAL DIAGNOSIS…
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Transient Global Amnesia:
- Acute
- Transient(prompt return of
memory)
- Recent memory is often impaired
- Highly complex mental & physical
acts are preserved
DIFFERENTIAL DIAGNOSIS…
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TGA can be differentiated from
dissociative amnesia:
- anterograde amnesia
- more upset and concerned
- personal identity is retained
- more generalized
- most common in 60s & 70s
DIFFERENTIAL DIAGNOSIS…
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Dementia: multiple cognitive deficits,
Delirium: altered consciousness,
impaired attention, fluctuation,
Cerebral infections & neoplasms
Metabolic disorders
….
DIFFERENTIAL DIAGNOSIS…
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Organic amnesias have several distinguishing
features:
- no recurrent identity alteration
- not selectively limited to personal
information
- do not focus on or result from an
emotionallt traumatic event
- more often anterograde than retrograde
DIFFERENTIAL DIAGNOSIS…
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Organic amnesias have several
distinguishing features….
- usually permanent (excluding
substance abuse, TGA, metabolic,
delirium,…)
- the erasure or destruction of
memory or not registration
DIFFERENTIAL DIAGNOSIS…
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Substance use disorders:
-
alcohol
sedative hypnotics
anticholinergics
steroids
lithium carbonate
beta blockers
hypoglycemic agents
marijuana
hallucinogens
pentazocine
- phencyclidine
DIFFERENTIAL DIAGNOSIS…
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Psychiatric disorders:
- depression
- PTSD
- acute stress disorder
- somatoform disorders
- sleep disorders
- factitious disorder
- malingering
Other dissociative disorders:
- fugue
- identity
COURSE & PROGNOSIS
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Recovery is usually complete and termination
may be rapid in localized or selective
subtypes
Recovery is usually gradual in generalized
subtype
Functional impairment varies from mild to
severe, depending on the extent of the
amnesia
The more acute & the more recent the
instance of dissociative amnesia, the more
likely & the more quickly it is to be resolved
TREATMENT
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Intrusive attempts to retrieve memories can
result in retraumatization if the patient is not
properly prepared
This risk is especially great for longstanding
or childhood-onset amnesias
The clinician should control the pace of
suggested recollection, usually within the
framework of a broader psychotherapy
In extreme cases, hospitalization may be
necessary
TREATMENT…
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Group psychotherapy: especially
successful in helping combat veterans
and survivors of childhood abuse
Hypnosis
Drug-assisted interview