AnnaLynne McCord has been diagnosed with dissociative identity disorder (DID).
The 'Nip/Tuck' actress explained how her career helped bring the condition - which was previously known as multiple personality disorder - to light.
She said: "All of my roles were splits, but I didn't even realise I was doing it at all until I did a project, '90210'. "
But it was only when she shot 2012 horror movie 'Excision' during a break from '90210' that she realised something wasn't right.
She added in an interview with Dr. Daniel Amen: "I played a very cerebral, disturbed, strange little girl that was very close to who I feel I am on the inside. It was very exposing, very confronting, probably a bit re-traumatising without realising it.
"The crazy thing about it was that I wrapped that film at 2 a.m. on a Tuesday and had to be happy, crazy Beverly Hills blonde bombshell on Wednesday at noon.
"I couldn't find her, she was not accessible. I was dark, I was very deep into this character Pauline, and I couldn't get [out]."
The actress recalled being "co-conscious" of her true identity and a split personality she dubbed 'Little Anna' when she was 13.
She said: "She was a balls to the wall, middle fingers to the sky, anarchist from hell who will stab you with the spike ring that she wears, and you'll like it. Then she'll make you lick the blood from it.
"She was a nasty little creature, but I have so much gratitude to her because she got me out of the hell that I was in."
AnnaLynne insisted she feels no "shame" about having the condition or any other part of her life's "journey" because she thinks that's the best approach to tackling trauma.
She said. "I am absolutely uninterested in shame.
"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."
The 33-year-old star previously told how being treated for PTSD after being raped as a teenager brought back memories of child sexual abuse and in the new interview, she discussed her memory loss.
She said: "I don't have anything until around five. Then from five 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."
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