Dissociative disorders usually develop as a way of dealing with trauma. They most often form in children exposed to long-term physical, sexual or emotional abuse. Natural disasters and combat can also cause dissociative disorders.

Symptoms and signs of dissociative disorders include:

• Significant memory loss surrounding a specific time period, person or and event
• Out-of-body experiences, such as feeling as though you are watching a movie of yourself
• Mental health problems such as depression, anxiety and thoughts of suicide
• A sense of detachment from your emotions, or emotional numbness
• A lack of identity

The symptoms of dissociative disorders depend on the type of disorder that has been diagnosed. There are three types of dissociative disorders defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM):

• Dissociative Amnesia. The main symptom is difficulty remembering important information about one’s self. Dissociative amnesia may surround a particular event, such as combat or abuse, or more rarely, information about identity and life history. The onset for an amnesic episode is usually sudden, and an episode can last minutes, hours, days, or, rarely, months or years. There is no average for age onset or percentage, and a person may experience multiple episodes throughout her life.
• Depersonalization disorder. This disorder involves ongoing feelings of detachment from actions, feelings, thoughts and sensations as if they are watching a movie (depersonalization). Sometimes other people and things may feel like people and things in the world around them are unreal (derealization). A person may experience depersonalization, derealization or both. Symptoms can last just a matter of moments or return at times over the years. The average onset age is 16, although depersonalization episodes can start anywhere from early to mid childhood. Less than 20% of people with this disorder start experiencing episodes after the age of 20.
• Dissociative identity disorder. Formerly known as multiple personality disorder, this disorder is characterized by alternating between multiple identities. A person may feel like one or more voices are trying to take control in their head. Often these identities may have unique names, characteristics, mannerisms and voices. People with DID will experience gaps in memory of everyday events, personal information and trauma. Women are more likely to be diagnosed, as they more frequently present with acute dissociative symptoms. Men are more likely to deny symptoms and trauma histories, and commonly exhibit more violent behavior, rather than amnesia or dissociative states. This can lead to elevated false negative diagnosis.

Dissociative identity disorder is a personality disorder

While dissociative identity disorder was previously referred to as multiple personality disorder, dissociative identity disorder is not a personality disorder. Instead, dissociative identity disorder is categorized as a dissociative disorder. Dissociative disorders involve loss of contact with oneself and usually begin in childhood, while personality disorders are characterized by a fixed pattern of personality traits that inhibit a person’s ability to live a normal, stable life.

People with dissociative identity disorder are violent

People with dissociative identity disorder are no more violent than the general population. While the idea of dissociative identity disorder violent alters has frequently been the premise of horror movies, it is not supported by what is known about dissociative identity disorder. There is no link between increased criminal activity and dissociative identity disorder. The false belief that people with dissociative identity disorder are violent is dangerous as it causes unnecessary fear, further stigmatizing and isolating people who have a serious mental illness.

Dissociative disorders are managed through various therapies including:

• Psychotherapies such as cognitive behavioral therapy (CBT) and dialectical behavioral therapy (DBT) (a modified version of CBT that healthy coping and emotional regulation) 
• Eye movement desensitization and reprocessing (EMDR)
• ​Medications such as antidepressants can treat symptoms of related conditions