Rare condition indicated by the absence of a clear and comprehensive identity. In most cases two or more independent and distinct personality systems develop in the same individual. Each personality may alternately inhabit the person's conscious awareness to the exclusion of the others, but one is usually dominant. The various personalities typically differ from one another in outlook, temperament, and body language and might assume different first names. The condition is generally viewed as resulting from dissociative mental processes—that is, the splitting off from conscious awareness and control of thoughts, feelings, memories, and other mental components in response to situations that are painful, disturbing, or somehow unacceptable to the person experiencing them. Treatment is aimed at integrating the disparate personalities back into a single and unified personality.
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