It’s one of the most common plot twists in Hollywood — caught red-handed, the murderer claims to suffer from multiple personality disorder, says he has no memory of the crime, and points the finger at an alternate personality.
A new study, however, suggests such a scenario belongs strictly to the realm of fiction.
The study — conducted by Harvard’s Richard J. McNally, Rafaele Huntjens of the University of Groningen, and Bruno Verschuere of the University of Amsterdam — casts doubt on the “amnesia barrier” that has long been a hallmark of what is now called dissociative identity disorder (DID) by demonstrating that patients do have knowledge of their other identities. Huntjens was lead author of the study, which was reported in a paper published in PLoS ONE on July 17.
“Ultimately, this disorder is a way of expressing distress,” said McNally, a professor in the Department of Psychology. “What we have shown is that a fundamental idea behind the concept of DID — that there is amnesia between identities — there’s no convincing evidence for that.”
Tip: @RichardWiseman on Twitter
There always seemed to be a bit of skepticism about this stated disorder. I’m pretty certain this won’t be the final word but I wonder if it signals a change in defining and treating patients. Ultimately, that’s for the good.