AnnaLynne McCord reveals she has dissociative identity disorder. Experts explain what that means.

AnnaLynne McCord revealed that she has dissociative identity disorder (DID), previously known as multiple personality disorder, a diagnosis the 90210 star feels no “shame” in sharing.

This month, McCord, 33, met with Dr. Daniel Amen, a Los Angeles-based psychiatrist to discuss her disorder, described by the American Psychiatric Association as the existence of two or more identities that cause changes in memory, behavior and emotions. In addition, each identity, which surfaces involuntarily and repeatedly, may have their own food likes and dislikes, clothing styles or hobbies. Other times, a person’s body may feel different with each identity — bigger or smaller or of another gender. "Ongoing gaps in memory about everyday events, personal information and/or past traumatic events" is another symptom.

“The way this is talked about is with so much shame and I am absolutely uninterested in shame,” McCord told Amen. “There is nothing about my journey that I invite shame into anymore. And that's how we get to the point where we can articulate the nature of these pervasive traumas and stuff, as horrible as they are."

Dissociative identity disorder was previously referred to as "multiple personality disorder," Stephen D. Benning, an associate professor of psychology at the University of Nevada, Las Vegas tells Yahoo Life. However, the DSM (Diagnostic and Statistical Manual of Mental Disorders) broadened the definition with the knowledge that not everyone with the disorder has distinct identities with unique life histories, and to differentiate between other personality disorders.

In McCord’s case, getting raped at age 18 triggered memories of her childhood sexual abuse. In 2017, the actress revealed to the BBC that a friend staying in her home had assaulted her while she slept. “My whole body shut down,” she told the outlet. “For ten years I thought it was my fault, I didn’t fight back.” McCord went on with her life, although she felt suicidal and engaged in self-harm behavior, even playing a rape victim on 90210, a storyline she valued, given her advocacy work with rape victims. McCord also said she had large gaps in memory, telling Amen, "I don't have anything until around 5. Then from 5 to 11, I recount incidents throughout. Then when I was 13, I have a singled-out memory that was one thing, but I don't have the sense of anything else at that time."

According to Helen Friedman, a clinical psychologist in St. Louis, Mo., who has studied the disorder for 40 years, it is a primitive defense that arises from childhood chronic trauma, as opposed to a singular incident that occurs while a child is in a consistently positive caregiving environment. "There can be very distinct, well-rounded 'alters' [alternative personalities] or fragments of others who come out for a single purpose," she tells Yahoo Life.

“In my history, you’ll see me just show up with a black wig and a new personality and I was this tough little ‘baddie,’” the Nip/Tuck actress told Amen. “And then I’d be the bohemian flower child.” For the most part, McCord said she embodied a “balls to the walls, middle fingers to the sky, anarchist from hell who will stab you with a spiked ring she wears and you’ll like it” personality adding, “She was a nasty little creature.”

However, as an actress hired to portray different characters, McCord did not realize that she had dissociative identity disorder until her role in the 2012 film Exicon. "I played a very cerebral, disturbed, strange little girl that was very close to who I feel I am on the inside,” she said. “It was very exposing, very confronting, probably a bit re-traumatizing without realizing it.” The day McCord wrapped the film, she “had to be happy, crazy Beverly Hills blonde bombshell” an uncomfortable transition on the heels of a darker project.

"To the extent that people are called on to play multiple roles in their lives, it may be easier to not recognize the possibility of having dissociative identity disorder," says Benning. "We all play different roles during the day, however, 'me' is still experienced as a continuity. The disorder differs in that there might be periods of life or every-day events that one can't recall. It's the amnesia that separates the disorder." And those close to a person with the disorder might not realize they have it, says Friedman.

Dissociative identity disorder can't be treated with medication. According to the International Society for the Study of Trauma and Dissociation, "Alters are recognized as legitimate aspects of the self that help cope with various life circumstances, and the goal is to achieve a working harmony or resolution among all alters if not a fusion of identities." Treatment also involves "carefully confronting and integrating trauma memories into a narrative of a person's past" and "coordinate functioning and cooperation among alternate identities in the present and future."

"And when we talk about the profound experience of multiple identities and dissociative amnesia, there is no singular neurotransmitter that could be addressed with pills," adds Benning.

McCord and Amen will work together going forward with McCord hopeful about her future. "For me, my heart is to change this narrative about the behaviors that follow trauma," she told the doctor. "And not responding to someone or judging someone for their actions, but asking, 'What happened to you? How did we get here?'"

If you or someone you know are experiencing suicidal thoughts, call 911, or call the National Suicide Prevention Lifeline at 1-800-273-8255 or text HOME to the Crisis Text Line at 741741.

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