Multiple Personality: The way that novelists experience their characters fulfills Diagnostic Criteria A & B, but not C in DSM-5 (the psychiatric diagnostic manual)

“Dissociative Identity Disorder

[Multiple Personality Disorder]

Diagnostic Criteria

A. Disruption of identity characterized by two or more distinct personality states, which may be described in some cultures as an experience of possession. The disruption in identity involves marked discontinuity in sense of self and sense of agency, accompanied by related alterations in affect, behavior, consciousness, memory, perception, cognition and/or sensory-motor functioning. These signs and symptoms may be observed by others or reported by the individual.

B. Recurrent gaps in the recall of everyday events, important personal information, and/or traumatic events that are inconsistent with ordinary forgetting.

C. The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning” (1, p. 292).

1. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Arlington, VA, American Psychiatric Association, 2013

In other words…

A. There are two or more identities, each with it own sense of self, its own sense of being able to think for itself, and its own characteristic pattern of emotions, behavior, awareness, etc. The existence and characteristics of these identities may be known only to the person, and reported by the person, or, if alternate identities come out, their characteristic thinking and behavior may be observed by others.

B. Some identities are aware of each other (co-conscious), but other identities are not. In the case of two identities who are not co-conscious, the period of time that one of them is in control or comes out will be experienced by the other identity as a memory gap.

C. Multiple personality is considered a mental illness only if it causes significant distress and/or dysfunction.

Comment

Once you understand the above, you realize that the diagnostic criteria for multiple personality are fulfilled when a novelist experiences a character who has a mind, etc., of its own, especially if the novelist sometimes switches into being the character, or, as novelist Philip Roth puts it, “impersonates” the character (search “Philip Roth”). But since, for most novelists, their multiple personality does not fulfill Criterion C, it cannot be considered a disorder (mental illness).

When a person fulfills criteria A and B, but the multiple personality is actually an asset rather than a liability—e.g., in writing novels—then I call it normal multiple personality (as opposed to multiple personality disorder).

Added November 18, 2019: What does it mean for a fiction writer to feel that a voice, character, or narrator in the writer's head has a mind of its own? It means that the voice, character, or narrator seems to have thoughts that the writer's regular personality does not recall thinking, which is a memory gap (criterion B in the diagnostic criteria). Also see: https://cpb-us-e1.wpmucdn.com/blogs.uoregon.edu/dist/7/8783/files/2014/07/TaylorHodgesKohanyi-130mpe0.pdf