Dissociative Identity Disorder: In the 1970s psychiatrist began to diagnose people with having ‘multiple personalities.’ In an attempt to define what ‘multiple personalities’ are more people were diagnosed with having ‘multiple personalities.’ At first, people would fit the expected symptoms but then cases diverged from the expected norm more and more. These deviations from the norm, for example, someone having 17 identified personalities rather than the norm of 2 -3, then got added to the diagnosis criteria and became part of the standard set of symptoms. It then became part of the therapy for having ‘multiple personalities’ for psychiatrists to try to elicit more and more alters, because it became expected that people had more alters.

The change to Dissociative Identity Disorder as the name of the condition marks an evolution in how the disorder is classified, patients are no longer expected to come with a whole lot of distinct personalities.