Psychologic trauma refers to events (such as sexual assault, major earthquake, or plane crashes) that overwhelm an individual's capacity to cope. Psychologic trauma can result in chronic and recurring dermatologic symptoms that persist after the trauma subsides. Examples are cutaneous sensory flashbacks (which may be fragments of the sensory component of the traumatic experience), autonomic hyperarousal (with symptoms such as profuse sweating or flare-up of an underlying stress-reactive dermatosis), conversion symptoms (such as numbness, pain, or other medically unexplained cutaneous symptoms), and cutaneous self-injury (manifesting in many forms, including trichotillomania, dermatitis artefacta, and neurotic excoriations--tension-reducing behaviors in patients who have posttraumatic stress disorder).