We propose a model of Post-Traumatic Stress Disorder (PTSD) symptoms in which they have positive evolutionary adaptational value in traumatic environments. The persistence of PTSD symptoms following return to more benign environments may result from biological changes within the organism, reflected by a primary response of increased levels of underlying traits such as Negative Affectivity. Secondary symptoms such as social withdrawal and substance abuse are conceptualized as subsequent coping with the primary trauma response. This model was tested using data on 413 former World War II Prisoners of War (POWs). The results were consistent with the model, indicating an enduring high level of Negative Affectivity as measured by scales on the MMPI. Capitivity severity scores, developed using a factor analysis of POW experience variables, were related to lifetime and current diagnoses of PTSD, generalized anxiety disorder, and major or minor depression. They were not related to schizophrenia, alcohol abuse/dependence, bipolar I and II disorders, or organic mental disorders. Elevated Negative Affectivity indicators were proportional to the captivity severity scores.
- evolutionary adaptation
- negative affectivity
- post-traumatic stress disorder
- prisoners of war