Fundamentally, there is no difference.
The fundamental concepts did not change, however some were expanded. Both terms explain the disorder as a splitting of the mind as a means, usually viewed as creative in nature, as a meant of coping with repeated trauma – commonly reported to be sexual. The mind is believed to have the capability to separate trauma experiences into distinct compartment or personalities or insiders and a variety of other terms that refer to alter states of being.
The term “multiple personality disorder” was renamed “dissociative identity disorder,” however most people who believe they suffer from this mental malady refer to themselves as “multiples.” There is a plethora of words to describe many parts and divisions within a multiple system, and each will be addressed separately in upcoming posts.
The renaming and redefining of multiple personality disorder – to – dissociative identity disorder came at a time when many former patients were filing legal suits against their treating psychiatrists and therapists for what amounted to medical malpractice. Multiple personality disorder was getting a bad rap and with the rise in successful litigation of malpractice suits, many therapists scattered and laid low.
Several therapists I know, for instance, left their place of employment and affiliated themselves with other institutions, went into private practice, or changed their psychotherapy focus. Some simply stopped advertising themselves as experts in this field. The practice did not stop, however. They continued to diagnose patients with some form of dissociation which often led back to multiple personalities.
Multiple personalities is one mind splitting into many. Dissociative Identity is the failure of many minds to be one. No matter which way the equation is presented, the result is the same.