Lanius, R.A., Vermetten, E., Loewenstein, R.J., Schmal, C., Brenner, D.J., & Spiegel, D. (2010). A dissociative subtype of PTSD: Clinical and neurobiological evidence. American Journal of Psychiatry, 167, 640-647.
Psychology’s daignostic nosology, the DSM-IV-TR, is currently under intense scrutiny by many professionals in the field as it is in the middle stages of revision (soon to be DSM5). In the current edition of the DSM-IV-TR, the diagnostic criteria for PTSD require that the victim demonstrate or report 1 symptom of re-experiencing (flashbacks, nightmares, intrusive thoughts & images, etc.), 3 symptoms of avoidance, and 2 symptoms of hyper-arousal (increased startle response, sleep disturbance, etc.). Although the largest symptom-requirement for PTSD falls under the avoidance category, symptoms of intrusive re-experiencing and physiological hyper-arousal are most commonly treated first and are often thought as the “hallmark” symptoms.
In the article cited above, Lanius and colleagues argue that the current DSM-IV-TR diagnostic criteria reflect a non-dissociative type of PTSD, or a type of PTSD in which there is an under-modulation of affect and re-experience and arousal symptoms predominate. They introduce the concept of a dissociative type of PTSD in which avoidance symptoms reflect the over-modulation of affect. The authors present clinical evidence to demonstrate that approximately 30% of those with PTSD show primarily dissociative symptoms, such as amnesia, avoidance, and numbing. Results of neuroimaging also support the conceptualization of a dissociative subtype of PTSD, with these more dissociated trauma survivors showing signs of heightened prefrontal cortical activity and reduced limbic activity in response to traumatic stimuli, while their more hyper-aroused counterparts showed the inverse pattern of results.
But what does this mean for those of us in the field, working with youngsters who have survived traumatic events? I would suggest that during routine clinical interviewing with parents and children, clinicians take care to assess for the severity not just of avoidance, but also of dissociation, and give fair consideration to whether the dissociation and avoidance reflect the primary reaction to the trauma as opposed to hyper-arousal and intrusive re-experiencing. In my own work with severely traumatized youth suffering from severe dissociation, I have found Dr. Frank Putnam‘s book, Dissociation in Children and Adolescents: A Developmental Perspective, especially helpful. Dr. Putnam’s book includes copies of diagnostic instruments, such as the Dissociative Experiences Scale, that are not copyrighted and that readers are encouraged to use in their own clinical assessment and treatment. Additional information for clinicians treating dissociative children for trauma-related anxiety can be found in the work of Dr. Janine Shelby and colleagues, most notably in the development of the Prescriptive Posttraumatic Play Therapy model.