Dissociative disorders are psychological disorders that involve a dissociation or interruption in aspects of consciousness, including identity and memory.1 Dissociative disorders include:

• Dissociative amnesia involves a temporary loss of memory as a result of dissociation. In many cases, this memory loss, which may last for just a brief period or for many years, is a result of some type of psychological trauma.
  Dissociative amnesia is much more than simple forgetfulness. Those who experience this disorder may remember some details about events but may have no recall of other details around a circumscribed period of time.
• Dissociative identity disorder, formerly known as multiple personality disorder, involves the presence of two or more different identities or personalities. Each of these personalities has its own way of perceiving and interacting with the environment. People with this disorder experience changes in behavior, memory, perception, emotional response, and consciousness.
• Depersonalization/derealization disorder is characterized by experiencing a sense of being outside of one’s own body (depersonalization) and being disconnected from reality (derealization). People who have this disorder often feel a sense of unreality and an involuntary disconnect from their own memories, feelings, and consciousness.