The controversial diagnosis of dissociative identity disorder
(DID) has replaced what once was called "multiple personality
disorder." People diagnosed with DID have trouble integrating
their memories, sense of identity, and aspects of consciousness
into a unified whole. New research supports the diagnosis and
sheds light on what may have gone wrong in patients' brains,
suggests David Spiegel, M.D. Spiegel, who chaired the
professional working group that recommended the change of name
in psychiatry's principle diagnostic manual, notes that the
disorder likely stems from trauma and can be considered a severe
form of post-traumatic stress disorder. Among the biological
markers he describes are a smaller hippocampus and certain
neurotransmitters. A better understanding of the importance of
specific regions of the brain to memory and emotion may help
push research forward. In pop culture, “multiple personality
disorder” is often portrayed as involving strategic, dramatic,
and seductive battles among personalities