About "Dissociation" and Personality Subselves
Mental-health workers generally agree that some people adapt to extreme and/or prolonged stress (pain, terror, shame, guilt, over-whelm, confusion) by "dissociating" from local personal and environ-mental realities. This may be a local or chronic survival response. Significant dissociative states are traditionally considered signs of "mental illness" and "Dissociative Disorders" in the DSM-IV index of abnormal mental-emotional conditions.
Premises - this protective stress-response is usually caused by one or more Guardian personality subselves like the Magician, Distracter, and Fantasizer, who are acting to comfort and protect one or more activated Inner Children. They "take over" the personality because they don't trust the resident true Self and other Regular subselves to protect the kids effectively. Subselves (brain regions?) seem to affect neuro-chemical balances and functioning, under some circumstances.
Lesson 1 in this nonprofit Web site offers more perspective and detail on personality subselves, and proposes "parts work" as an effective way to empower the resident true Self to gain other subselves' trust to manage stress in a healthier way than "dissociating."