Dissociative Identity Disorder

Dissociative Identity Disorder is a complex and intriguing disorder that is constantly being investigated. The perception on DID has evolved over time, from skeptics calling it false, to DID being classified as purely psychological to now, a time where advancements in technology have allowed scientists to explore the neurobiological aspects of the disorder. DID is a disturbance to the victims identity, memory and consciousness. It is classified as a person with two or more identities. The disorder is mostly found in women, and usually results from trauma at a young age such as physical or sexual abuse.

Disruption of at least some memory functions is an important aspect of DID, and in fact one of the DSM-IV criteria is the inability to recall important personal information that is too extensive to be explained by ordinary forgetfulness (DSM IV).

According to Ellenberger, amnesia between identities can be classified as follows: identities which are mutually cognizant of each other (no between-identity amnesia), identities which are mutually amnestic (interidentity amnesia as Huntjens refers to it), and identities which are one-way amnestic. The latter means that identity A has awareness of the experiences of identity B, while identity B has no knowledge of the experiences of identity A. Modern clinical observations show that all these variations can exist in one DID patient. A recent classification based on 100 cases of DID was made by Putnam. The majority of cases (72%) had at least one identity that denied the existence of other identities. Even more cases (86%) had an identity that claimed to be aware of all other identities (Putnam).

Clinical observations and descriptions of DID patients indicate that amnesia is normally restricted to episodic memory, i.e., memory for autobiographical events and personal experiences. Episodic memory can be divided into explicit and implicit memory. Explicit memory is the person’s conscious, intentional recollection of...