Dissociative amnesia occurs when someone blocks specific information, usually associated with a stressful or traumatic event.

Losing keys, getting lost or not being able to remember certain events from the past can be frustrating. Some people may experience forgetfulness when trying to recall something and search for hints to refresh their memory. However, a traumatic experience may prompt some people’s forgetfulness, causing great difficulty with normal tasks.

Dissociative amnesia disorder mentally separates a person from some stages of their lives. Following some trauma or severe stress, dissociative amnesia may disconnect the individual from memories surrounding certain events or people. This abnormal memory loss can significantly affect their lives. A person may only forget a specific event, or it may be so extreme that they forget who they are. Unlike patients who develop medical amnesia after an injury or stroke, dissociative amnesia patients rarely show concern about their disorder.

What Is Dissociative Amnesia?

In terms of a dissociative amnesia definition, this specific disorder is in an umbrella group of conditions called dissociative disorders. Dissociative disorders are mental illnesses that affect the way the brain works and reacts. This disorder involves disruptions of memory, consciousness, identity and perception. When disruption to these systems occurs, it can change the way a person functions.

Dissociative amnesia occurs when someone blocks specific information, usually associated with a stressful or traumatic event. This style of amnesia may leave the individual unable to recall important personal information. The memories still exist; however, they are deeply buried within the person’s mind. The memories might reemerge on their own when stimulated by certain surroundings.

Types of Dissociative Amnesia

A person with dissociative amnesia may not remember the trauma that caused the disorder. Additionally, dissociative amnesia has several subtypes:

  • Localized
  • Selective
  • Generalized
  • Systemized
  • Continuous

Localized Amnesia

With localized amnesia, memory loss affects a specific period during a person’s life, such as during childhood, or memories attached to a specific friend or family member. Often, the memory loss revolves around a specific trauma and the narrow period following the traumatic event. The forgotten period may be between a few hours to a few days. If an individual survived the World Trade Center attacks, they might not remember how they got out of the building or how they got home that day.

Selective Amnesia

Selective amnesia involves forgetting only parts of a traumatic event during a specific timeframe. The patient may not remember the entire situation of the event, though they can remember some specific details. For example, an abuse victim may remember being on vacation but not the abuse that took place there. A war veteran may recollect details, such as eating a meal on the run or shooting toward the enemy but may not recall losing their friend to a grenade. Common elements forgotten with selective amnesia include relationships, unique talents or abilities, concerts events or traumatic events.

Generalized Amnesia

With generalized amnesia, patients forget their identity and may not be able to recall anything about their life. These individuals may forget their history, who they are, what they have done or what they have experienced. Some patients can no longer access learned skills and forget information they already knew. Generalized dissociative amnesia is a rare type of amnesia that is common among combat veterans, sexual assault victims and individuals experiencing extreme stress.

Systematized Amnesia

In systematized amnesia, patients forget specific categories of information, such as all information about an individual or their family. This amnesia covers only certain classes of information, such as all memories related to a location or a person in their past. An individual with this type of amnesia may forget all the details about a family member who abused them.

Continuous Amnesia

Continuous amnesia occurs when the individual has no memory of events occurring after a particular event. Patients forget each new event as it occurs. Unlike generalized amnesia, in continuous amnesia, the individual is still aware of their surroundings.

Symptoms of Dissociative Amnesia

A common symptom of dissociative amnesia is the inability to remember certain past experiences or personal information. Misplacing keys or forgetting someone’s name a few times would not be categorized as amnesia. Dissociative amnesia may cause confusion as well as depression and anxiety.

Dissociative amnesia symptoms may include:

  • Forgetting personal information about oneself
  • Blocking out specific traumatic events
  • Not remembering certain friends, family members or coworkers
  • Have trouble recalling incidents following a traumatic event

Most situations of dissociative amnesia are temporary, though memory gaps can last anywhere from a few minutes to an entire lifespan.

Causes of Dissociative Amnesia

Dissociative amnesia can be a very confusing disorder for people to understand and many people do not know what causes the disorder. The most common dissociative amnesia causes include:

  • Past or recent trauma
  • Abuse
  • Accidents
  • Extreme stress
  • War or a natural disaster, either witnessed or experienced

Although the symptoms are similar, dissociative amnesia and amnesia resulting from brain damage are not the same. There are abnormal changes in brainwave activity among individuals with dissociative amnesia.

How Is Dissociative Amnesia Diagnosed?

When someone experiences dissociative amnesia symptoms, they can see a physician, who may evaluate the individual’s medical history and complete a physical exam. There are currently no dissociative amnesia tests or lab tests to diagnose dissociative disorders, though certain conditions such as brain diseases, head injuries, intoxication and sleep deprivation can lead to similar symptoms to dissociative amnesia.

An individual may seek treatment from a psychiatrist or psychologist if they cannot find a medical illness. These professionals are trained to treat mental illnesses and use specially designed interview and assessment tools to test an individual for dissociative amnesia.

Who Is at Risk for Dissociative Amnesia?

People who experience consistent abuse during childhood may face a high risk of developing dissociative disorders. The type of abuse is not specific, and risk is high with physical, emotional and sexual abuse. Overall, dissociative amnesia is more common among women than men.

Dissociative Amnesia Statistics

According to dissociative amnesia statistics, only about 2 percent of Americans experience meet the criteria for dissociative disorders. Other key facts and statistics about dissociative amnesia include:

  • Dissociative amnesia is a relatively rare condition that impacts about 2.6 percent of women and 1 percent of men in America.
  • There is a greater chance of experiencing dissociative amnesia when other factors have occurred, such as abuse, torture or experiencing a natural disaster.
  • Partial memory loss is common among veterans who have either witnessed a combat injury or experienced it themselves. An immediate intervention after a traumatic event may diminish the chance of dissociative disorder from developing.

If you or a loved one needs treatment for a drug or alcohol addiction and a co-occurring mental illness or dissociative disorder, The Recovery Village can help. You can receive help from one of the facilities located throughout the country. To learn more about comprehensive treatment for co-occurring disorders, call The Recovery Village to speak with a representative.

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Editor – Camille Renzoni
Cami Renzoni is a creative writer and editor for The Recovery Village. As an advocate for behavioral health, Cami is certified in mental health first aid and encourages people who face substance use disorders to ask for the help they deserve. Read more
Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.