“As an undergraduate student in psychology, I was taught that multiple personalities were a very rare and bizarre disorder. That is all that I was taught on ... It soon became apparent that what I had been taught was simply not true. Not only was I meeting people with multiplicity; these individuals entering my life were normal human beings with much to offer. They were simply people who had endured more than their share of pain in this life and were struggling to make sense of it.”
― Deborah Bray Haddock, The Dissociative Identity Disorder Sourcebook
The DSM-5 gives the following criteria for a diagnosis of dissociative identity disorder:
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.
D. The disturbance is not a normal part of a broadly accepted cultural or religious practice. Note: In children, the symptoms are not better explained by imaginary playmates or other fantasy play.
E. The symptoms are not attributable to the physiological effects of a substance (eg, blackouts or chaotic behavior during alcohol intoxication or other medical condition, eg, complex partial seizures) (American Psychiatric Association, 2013)1.
Criterion A refers to the presence of at least one alter (distinct personality state) in addition to the main, or host, personality. The alter(s) may sometimes be mistaken for spirits and the experience of dissociation for one of possession. Alters must view themselves as more than different aspects of one complete person; alters each have their own perception of themself as a unique individual or entity. Alters can have different degrees of emotional expressiveness, behave in different ways, experience consciousness in different ways, have different memories, perceive themselves and the world around them in different ways, think in different ways and have different cognitive skills, and have different skills and abilities related to sensory-motor functioning. Others may have noticed these differences (for example, the individual might switch during a diagnostic interview or friends and family of the individual might have told them about their alters’ behaviors) or the individual might have noticed these changes within themselves due to finding evidence of their alters’ activities or due to the ability to remain co-conscious with their alters.
Criterion B refers to the inability of one or more alters to remember things that one or more other alters have experienced. This specific type of dissociative amnesia is most commonly associated with amnesia for every day events in which an alter other than the current alter was present. This is what leads to some dissociative individuals finding evidence of their time loss in the form of clothing or other items that they apparently own but don’t recognize, journal entries or sticky notes in their handwriting that they don’t remember writing, or insistent strangers calling them a name that isn’t theirs. This criterion can also be fulfilled by alters being unable to recall pertinent personal information such as the body’s age, current residence, or spouse. However, this criterion is generally not considered fulfilled just because the host or other alters are unable to recall trauma that spanned for years of their childhood and created their DID. That alone would not point to inter-identity amnesia and so would result in a diagnosis of other specified dissociative disorder subtype 1. This criterion cannot be fulfilled by incidents that can be explained by ordinary forgetting.
Criterion C refers to the fact that DID is a disorder. If a condition doesn’t cause distress or impairment, it is not a disorder and does not belong in the DSM-5. This criterion is present in the criteria of over half of all DSM-5 diagnoses in order to reduce the rate of false positive diagnoses given for non-clinically significant symptoms.
Criterion D excludes presentations that mimic DID due to culture or religion (such as a spiritual leader acting as a medium as part of cultural ceremonies) or due to imaginary play.
Criterion E excludes presentations and symptoms that are due to organic, physiological, or situational causes. For example, blacking out while drunk is not an example of amnesia that meets Criterion B, and feeling like a different person while experiencing an altered consciousness due to a seizure is not an example of Criterion A.
1 American Psychiatric Association. (2013). Dissociative Disorders. In Diagnostic and statistical manual of mental disorders (5th ed.). http://dx.doi.org/10.1176/appi.books.9780890425596.dsm08