Dreaming in posttraumatic stress disorder: A critical review of phenomenology, psychophysiology and treatment.

This review summarizes the available knowledge on the phenomenology of posttraumatic dreams. Posttraumatic nightmares are reported by up to 70% of individuals suffering from posttraumatic stress disorder (PTSD). An extensive review of polysomnographic studies suggests that neither this high incidence nor the occurrence of posttraumatic nightmares throughout the sleep cycle can be explained by altered REM sleep parameters. The assumption that a reduction of dream recall may serve as a coping mechanism in PTSD patients is questionable. About 50% of posttraumatic dreams comprise exact replications of the traumatic events. Therefore dreams in PTSD do not have stereotypical content. Data characterizing non-replicative posttraumatic dreams and indicating a change in dream content over time must be considered preliminary. Occurrence of posttraumatic dreams is associated with psychopathological developments. Imagery Rehearsal Therapy has repeatedly been proven to be a valuable tool in treating patients suffering from posttraumatic dream disturbance. A deeper knowledge of posttraumatic dreams is essential for any theory of PTSD as well as for a better understanding of the overall function of dreaming.