Dissociation refers to an altered state of consciousness in which the individual feels detached from the body or self. This process may be voluntary or involuntary, and can be adaptive when resistance or escape from a life threatening situation is not possible.
Other /More definition:
Dissociation may be defined as:
(1) a process whereby different facets of an individual's sense of self, memories, or consciousness become split off from one another.
(2) an altered state of consciousness in which the individual feels detached from the body or self. This process may be voluntary or involuntary, and can be adaptive when resistance or escape from a lifethreatening situation is not possible.
(3) a separation between functional contributions of two (2) different brain areas.
(4) a sense of separateness or withdrawal from others; an inability to experience the bond of mutual commitment.
(5) a situation that occurs as a result of brain damage in which one function is present and another is absent.
In psychology and psychiatry, a perceived detachment of the mind from the emotional state or even from the body. Dissociation is characterized by a sense of the world as a dreamlike or unreal place and may be accompanied by poor memory of the specific events, which in severe form is known as Dissociative amnesia. The term Dissociation refers to the act of separating or the state of being separated.
See also Double Dissociation; Single Dissociation.