Dissociation in posttraumatic stress disorder part I: Definitions and review of research.

Abstract

Since Janet wrote about dissociation in the early 1900s, the relationship between traumatic stress and dissociation has been discussed and debated in the fields of psychology and psychiatry. In the last 25 years, research has been conducted that allows empirical examination of this relationship and the question of how dissociative symptoms are related to posttraumatic stress disorder (PTSD). After defining the types of dissociative experiences that are considered most relevant to PTSD, we present a comprehensive and systematic review of research addressing the relationship between dissociation and traumatic stress; the rise in dissociation after traumatic stress and its subsequent decline over time; the relationship between dissociation and symptoms of PTSD in nonclinical, clinical, and PTSD samples; the conditional probability of high PTSD symptoms when dissociation level is high; the relationships among dissociation and re-experiencing, avoidance, and hyperarousal symptoms of PTSD; and biological studies of dissociation in PTSD.