Posttraumatic Stress Disorder (PTSD)
Posttraumatic Stress Disorder (PTSD)
Posttraumatic stress disorder (PTSD) now sits within the newly created “Trauma- and StressorRelated Disorders” section of the Diagnostic and Statistical Manual of Mental Disorders (fifth edition; DSM-5). Through the refinement and expansion of diagnostic criteria, the DSM-5 version better clarifies the broad and pervasive effects of trauma on functioning, as well as the impact of development on trauma reactions. Aggressive and dissociative symptoms are more thoroughly characterized, reflecting increasing evidence that reactions to trauma often reach beyond the domains of fear and anxiety (these latter domains were emphasized in DSM-IV). These revised criteria are supported by decades of preclinical and clinical research quantifying traumatic stress– induced changes in neurobiological and behavioral function. Several features of the DSM-5 PTSD criteria are similarly and consistently represented in preclinical animal models and humans following exposure to extreme stress. In rodent models, for example, increases in anxiety-like, helplessness, or aggressive behavior, along with disruptions in circadian/neurovegetative function, are typically induced by severe, inescapable, and uncontrollable stress. These abnormalities are prominent features of PTSD and can help us in understanding the pathophysiology of this and other stress-associated psychiatric disorders. In this article we examine some of the changes to the diagnostic criteria of PTSD in the context of trauma-related neurobiological dysfunction, and discuss implications for how preclinical data can be useful in current and future clinical conceptualizations of trauma and trauma-related psychiatric disorders. Keywords animal models; DSM-5; plasticity; posttraumatic stress disorder; stress; trauma Correspondence: Susannah Tye, PhD, Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN 55905. [email protected]. Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article. The views presented here do not necessarily reflect those of the US Department of Veterans Affairs or the US government. U.S. Department of Veterans Affairs Public Access Author manuscript Harv Rev Psychiatry. Author manuscript; available in PMC 2015 August 20. Published in final edited form as: Harv Rev Psychiatry. 2015 ; 23(1): 51–58. doi:10.1097/HRP.0000000000000035. VA Author Manuscript VA Author Manuscript VA Author Manuscript The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) includes important changes to the diagnostic criteria for posttraumatic stress disorder (PTSD). Although many of the symptoms remain consistent with DSM-IV-TR, the disorder has been moved to a new section entitled “Trauma- and Stressor-Related Disorders,” and the changes to the diagnostic criteria and their descriptions have expanded the section from just over one page to four pages. Much of the additional information is included under a subsection, “Posttraumatic Stress Disorder for Children 6 Years and Younger,” reflecting the greater attention to developmental differences in the manifestation of trauma symptomatology. Other key changes include: (1) removal of the requirement that the individual responded with fear, helplessness, or horror at the time of the trauma, (2) renaming the “re-experiencing” cluster symptoms as “intrusion” symptoms, (3) separating “avoidance” and “numbing” symptoms into two separate clusters, (4) subsuming “numbing” symptoms under a newly developed symptom cluster, “negative alterations in cognitions and mood,” (5) elaborating upon the “irritability or outbursts of anger” symptom to highlight the occurrence of verbal and physical aggression, (6) adding a specifier for a dissociative subtype. These modifications represent at least two important changes in the conceptualization of how individuals respond to overwhelming trauma. First, the development of a separate category for trauma- and stressor-related disorders takes an important step toward acknowledging that trauma often has broad and pervasive effects on functioning beyond what can be adequately captured in a single diagnosis. Coupled with the greater emphasis on aggressive and dissociative symptoms within the diagnosis of PTSD, the presence of this new section reflects a deeper understanding that reactions to trauma can be pervasive and diverse, and that they often reach beyond our previous conceptualization of them as being limited to the domains of fear and anxiety, which DSM-IV emphasized.1–16 Second, the inclusion of reactive attachment disorder and disinhibited social engagement disorder in the trauma- and stressor-related disorders section, coupled with the elaboration of the description of trauma symptoms in children within the PTSD criteria, begins to integrate the decades of preclinical and clinical research demonstrating the profound impact that developmental timing of trauma exposure has on trauma reactions, both at the time of initial exposure and in response to stress and trauma experienced later in life.17–31 In this article we examine changes to the diagnostic criteria of PTSD in the context of animal models of trauma-related neurobiological dysfunction, and discuss implications for how preclinical data can be useful in current and future clinical conceptualizations of trauma and traumarelated psychiatric disorders.
