Dissoziative Identitätsstörung

Dissociative Identity Disorder, or DID, formerly called multiple personality disorder, occurs when an individual exhibits two or more distinct personality states or alter. For instance, an individual may act formal and reserved at one moment and then loud and outgoing the next.

Further, these alters vary in memories, emotions, and behaviors, often causing memory gaps or difficulty recalling daily events.

Researchers have identified differences among alters in respiration rates, brain wave activity, eyeglass prescriptions, handedness, skin conductance, voice patterns, and handwriting.

Psychological factors like extreme childhood trauma, such as abuse, often cause individuals to compartmentalize distressing memories into separate identities.

Psychodynamic theorists see DID as a defense against unacceptable impulses, with a second identity expressing them, while learning theorists view it as anxiety-reducing behavior.

Sociocultural influences, such as increased media exposure, have shaped how people perceive and diagnose DID, leading to more cases.

DID often involves abnormal brain activity, with shrinkage in memory and threat detection areas and increased activity in regions inhibiting traumatic memories.