What You Should Know About Dissociative Identity Disorder

Dissociative identity disorder (DID) is a widely misunderstood condition (via Dialogues in Clinical Neuroscience). Formerly known as "multiple personality disorder", its legitimacy as a psychiatric illness was once questioned by clinicians who believed it was simply a more severe presentation of borderline personality disorder (BPD). Although DID and BPD share some similarities and can co-occur in patients, research shows that they're two distinct conditions with different psychological profiles and symptoms (via Harvard Review of Psychiatry).

DID affects up to 1.5% of Americans, per Harvard Review of Psychiatry. The disorder involves the existence of two or more separate personality states that tend to emerge at different times. Each personality state may have a different name, gender, voice, personal history, and set of behaviors, notes Mayo Clinic. People with DID often have significant gaps in their memory. They may not be able to remember their other identities, and may struggle to recall information about themselves, their experiences, or their day-to-day activities.

Due to its complicated and controversial history, there are still many myths and misconceptions surrounding DID. Here are some things you may not know about the condition.

People with DID usually experience memory loss

It's common for people with DID to have amnesia, notes the American Psychiatric Association. While this can vary in severity and scope, it generally takes a toll on the individual's quality of life and daily functioning.

One of the main symptoms of DID is dissociation. A mild form of this is daydreaming, whereby an individual gets lost in their thoughts. On the more severe end of the spectrum, a person may become disconnected from their environment and feel detached from reality. Dissociation can cause significant confusion and lapses in memory. People may forget personal information and day-to-day events, reports a study published in the European Journal of Psychotraumatology.

Amnesia has been found to be associated with reduced hippocampal volume in people with DID (via Psychological Medicine). Impairment is most notable in the CA1 region of the hippocampus, which plays a critical role in memory consolidation, particularly of autobiographical memories. Researchers theorize that childhood trauma, specifically emotional neglect, makes this part of the brain vulnerable to the damaging effects of stress, causing "fragmentation of the mind and a scattered sense of self".

DID is often rooted in childhood trauma

Those affected by DID often report a history of childhood abuse. Incidents of sexual abuse tend to be the most common, according to a paper published in the journal Psychiatry (Edgmont). Dissociation is believed to serve as a natural protective mechanism by allowing the individual to reduce awareness during a traumatic event, notes the American Psychiatric Association. People often switch identities — also known as "alters" — when they feel psychologically threatened.

Personality states are usually constructed when a child is more susceptible to having imaginary companions. Dissociating then becomes a go-to defense strategy in difficult situations. At a later stage in life, trauma is more likely to lead to post-traumatic stress disorder (PTSD) symptoms than to a dissociated identity, suggests Psychiatry (Edgmont).

Although it may not be possible to say with certainty why someone develops DID, 90% of people with the condition have experienced some form of abuse or neglect in their childhood, reports the American Psychiatric Association, drawing on data from the United States, Canada, and Europe.

DID involves various changes in the brain

According to a study published in PsyCh Journal, a woman with DID exhibited different brain activity as she switched between blind and sighted personality states. When her blind alter was in control, brain activity associated with sight was absent, even with her eyes open. Though, fascinatingly, typical brain activity resumed once her sighted alter took over.

Researchers have identified a number of structural and functional changes in DID patients' brains. When compared to healthy controls, people with DID have smaller volumes in various areas of the brain including the hippocampus, which is involved in memory and learning; the amygdala, a key player in emotional processing; and the frontal structures, which play a vital role in movement execution (via European Journal of Trauma & Dissociation).

Neuroimaging studies have shown that the brain looks different when it's dissociating (via PLoS One). There are unique neural patterns in people with DID during the process of dissociation. However, the specific neural underpinnings of dissociation need more investigation.

People can suffer for years without a diagnosis

The average age of onset for DID is somewhere between 5 and 10 years old, per Psychiatry (Edgmont). However, most people don't get diagnosed with DID until around age 30. A large number of patients eventually enter into treatment because of psychotic-like or somatic symptoms that become impossible to overlook.

Even though the signs of DID usually emerge in childhood, it can take people years to seek help and receive a diagnosis, note researchers (via European Journal of Trauma & Dissociation). Many people experience tremendous shame around their illness. Trauma specialists deem DID a "disorder of hiddenness" because patients are often reluctant to disclose their dissociative symptoms and tend to undermine their significance (via Frontiers in Psychology). Some experts even attribute the memory gaps that people experience to feelings of shame or guilt.

However, DID is a serious disorder, warns Psychiatry (Edgmont). So, it's important that individuals with the condition receive the medical attention and support that they need.

It's possible to treat DID

One of the most common interventions for DID is psychodynamic psychotherapy (via European Journal of Psychotraumatology). This approach usually has three phases: symptom stabilization, processing of traumatic memories, and identity integration and rehabilitation. A key goal of the treatment is to establish harmony between the patient's identities, with the hope of gradually merging into one whole, integrated personality. But recovery can look different for everyone. 

Cognitive behavioral therapy (CBT) is also recommended for DID, per Psychiatry (Edgmont). It can help patients adjust their cognitions about themselves and the world, and find healthier coping strategies than dissociation.

Eye movement desensitization and reprocessing (EMDR) is another treatment used for patients with DID, per MIND. When the standard EMDR approach is adapted for use with people with dissociative disorders, it can help people process distressing memories and flashbacks. Alternatively, some people find relief in medication such as antidepressants.

While there is no cure for DID, it's possible for people to recover with the right kind of support. A combination of treatments can usually reduce symptoms or help individuals manage their difficulties. And over time, patients can gain some control of their behaviors and function more efficiently in their day-to-day lives.