PTSD and autism spectrum disorder: Co-morbidity, gaps in research, and potential shared mechanisms

Background: While autism and trauma were often linked in psychoanalytic theory, very few scientific attempts have been made to explore the associations and comorbidity between the two. Instead, each area has grown separately, yielding large bodies of theoretical and clinical knowledge. Theoretical framework: In this article, we suggest several possible pathways that may link trauma and autism. First, autism spectrum disorder (ASD) may serve as a vulnerability marker for posttraumatic stress disorder (PTSD), specifically by increasing the risk for exposure to traumatic events. Second, PTSD, once it has appeared, may exacerbate certain ASD symptoms, for example, through maladaptive coping strategies and reduced help-seeking. Third, there may be shared underlying mechanisms for PTSD and ASD, including neurological abnormalities associated with both disorders, as well as cognitive and behavioral mechanisms, such as increased rumination, cognitive rigidity, avoidance, anger, and aggression. In addition, the unique characteristics of ASD may determine which events are experienced as particularly traumatic (e.g., social insults and degradation, sensory overstimulation, abrupt changes in known routines) and affect both the manifestation and severity of posttraumatic sequelae among diagnosed individuals. Conclusions and recommendations: Research conducted separately in the areas of PTSD and ASD strongly suggests several potential pathways connecting both disorders. We conclude that there is a pressing need for more PTSD-ASD research, focusing not only on the prevalence of traumatic stress in individuals with autism, but also on their potentially unique perception of traumatic events, particularly from the social sphere. Such research may carry important clinical implications.