A conversation I had with my mother over the weekend prompted this. I think it’s a pretty common misconception that schizophrenia is the same as multiple personalities. I know ever since I was little I heard schizophrenia and “split personality” used interchangeably and while some multiples do exhibit behaviors which are similar to schizophrenia they are not the same thing. In fact the DSM-IV says that exactly (”schizophrenia is neither “split personality” nor “multiple personality.” Furthermore, people with schizophrenia are not perpetually incoherent or psychotic”), and then goes on to say:

Schizophrenia is characterized by profound disruption in cognition and emotion, affecting the most fundamental human attributes: language, thought, perception, affect, and sense of self. The array of symptoms, while wide ranging, frequently includes psychotic manifestations, such as hearing internal voices or experiencing other sensations not connected to an obvious source (hallucinations) and assigning unusual significance or meaning to normal events or holding fixed false personal beliefs (delusions). No single symptom is definitive for diagnosis; rather, the diagnosis encompasses a pattern of signs and symptoms, in conjunction with impaired occupational or social functioning (DSM-IV).

However what it says about multiple personalities (or dissociative identity disorder).

is a psychiatric diagnosis that describes a mental illness in which a single person displays multiple distinct identities or personalities, each with its own pattern of perceiving and interacting with the environment. The diagnosis requires that at least two personalities routinely take control of the individual’s behavior with an associated memory loss that goes beyond normal forgetfulness; in addition, symptoms can not be due to substance abuse or medical condition. (DSM-IV)

So, there we are, distinctly different. Just to clarify.