Multiple Personality, Schizophrenia, Psychosis, Dissociative Disorders, Trauma Spectrum Disorders: How are all related? What is the practical conclusion?

Eugen Bleuler, MD, the psychiatrist who coined the term “schizophrenia,” acknowledged that it is a heterogenous “group of schizophrenias.” In that diverse group, he included some patients who actually had multiple personality. But the psychiatrists who were interested in psychosis, per se, were not interested in multiple personality, and so they paid no attention.

Today, psychologists and psychiatrists who do have an interest in both multiple personality and psychosis, have various opinions:

Andrew Moskowitz, PhD, questions the validity of the diagnosis of schizophrenia. He argues that its psychotic symptoms may be traumatic in origin and dissociative—related to dissociative disorders, like multiple personality—in kind. However, “our analysis does not necessarily mean that schizophrenia is best conceptualized as a dissociative disorder. Rather, we hypothesize that some persons develop psychotic symptoms precisely because their capacity to handle traumatic or highly emotional experiences via dissociative mechanisms is limited” (1, p. 529).

Vedat Sar, MD, says that multiple personality may sometimes look quite psychotic for various reasons: a persecutory alternate personality may make the host personality look paranoid; there may be a psychotic alternate personality; the host personality may hear the voices of alternate personalties conversing; the host personality may be mysteriously made to have various emotions and behaviors by alternate personalities who are pulling the strings from behind-the-scenes. He says that a crisis involving various kinds of unrecognized multiple personality symptoms may produce episodes of “dissociative psychosis” (1, p. 540).

Barry Nurcombe, MD, FRANZCP, FRACP, speaking about adolescent psychiatric inpatients, describes “dissociative hallucinosis” as one of the “trauma spectrum disorders” (1, p. 553).

Colin A. Ross, MD, FRCPC, quotes both Bleuler and recently published case histories that purport to be about schizophrenia, but describe clear-cut multiple personality (1, pp. 559-562). He speaks of a dissociative subtype of schizophrenia that is trauma-induced.

Comment: As a practical matter, you should know that some people who are diagnosed and treated as having schizophrenia might be better understood and treated as having multiple personality.

1. Paul F. Dell, PhD and John A. O’Neil, MD, FRCPC (Editors). Dissociation and the Dissociative Disorders: DSM-V and Beyond. New York, Routledge, 2009.