Definition and Diagnosis
Dissociative amnesia is characterized by an inability to recall important autobiographical information, usually of a traumatic or stressful nature, that is inconsistent with ordinary forgetting and is not attributable to a substance or medical condition.
Epidemiology
Dissociative amnesia is one of the more commonly diagnosed dissociative disorders, with prevalence estimates varying by population studied, and it is often associated with exposure to trauma or overwhelming stress.
Risk Factors
Risk factors include exposure to a traumatic or highly stressful event, a history of childhood trauma, and pre-existing vulnerability to dissociative responses under stress.
Symptoms and Subtypes
The core symptom is memory loss for specific events or periods of time, most often related to trauma, which may be localized (a specific period), selective (parts of a period), or, less commonly, generalized to the person's entire life history.
Diagnosis
Diagnosis requires an inability to recall important autobiographical information inconsistent with ordinary forgetting, causing distress or impairment, and not better explained by another dissociative disorder, substance use, or a neurological or other medical condition.
Treatment
Treatment focuses on establishing safety and stabilization, followed by trauma-focused psychotherapy; recovery of memories, when it occurs, is approached cautiously and gradually to avoid re-traumatization, with the priority on functioning rather than forced memory retrieval.
Prognosis
Localized amnesia often resolves once the individual is removed from the stressful or traumatic context and receives appropriate support, though course can be more prolonged in cases with ongoing trauma exposure or generalized amnesia.
Reference
American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.).