In an interview with Good Morning America, the 90210 star recalled filming a season 2 scene for The CW series in which a teacher, played by Hal Ozsan, rapes her character Naomi.
"My whole body like just went into panic mode as if I was living out my life on camera," McCord said. "These moments were coming to light through my work. I didn't understand anything about the mind or the brain at the time, I was just trying to do my job and I couldn't."
McCord explained that though she had an intense emotional reaction around this scene, she didn't have the memories associated with her pain. Eventually, she learned she was a sexual abuse survivor, and that she had "all of the dangerous, toxic, harmful memories" locked away.
Given the great deal of misinformation about dissociative identity disorder—characters in films like Split depict those with the diagnosis as having distinct different personalities and identities—McCord explained what it means for her.
"You have fragments of yourself," she said. "There's AnnaLynne, who's talking to you right now, right? And then there's the part of me that this trauma happened to that still, if you can imagine it like trapped in Pandora's box and I just opened Pandora's box."
She continued, "The brain doesn't care about quality of life. It just cares about going on to continue living. I want my quality of life to get better and that's why I stepped into this healing process."
AnnaLynne first spoke about her diagnosis earlier this month in a conversation with Dr. Daniel Amen of the Amen Clinics.
"My doctor—it's a massive spectrum obviously, right—but she said that I had it pretty seriously," she explained in the video. "And my splits before my memories came back, I had definitive splits. In my history, you'll see me, you know, I just show up with a black wig and a new personality and I was this tough little baddie and then I'd be the bohemian flower child. And also being an actress, my ability to split, all of my roles were splits."
She spoke about how playing her character Pauline in the 2012 film Excision helped her realize what was happening.
"I played a very, like, 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, maybe even a bit healing as well through some of it."