Wanting, Liking, and Missing Out: Exploring the Role of Reward Functioning in the Overlap Between PTSD and Depression.

ABSTRACT: Diminished reward functioning (anhedonia) is an aspect of multiple psychiatric diagnoses and is a critical component of depression, yet it has rarely been examined in the context of posttraumatic stress disorder (PTSD). Deficits in reward function may be a transdiagnostic factor contributing to the high rate of comorbidity between PTSD and depression. The present study examined the commonality and distinction between PTSD and depression and their relationship to reward functioning using a bifactor model in a sample of 106 trauma-exposed undergraduates. Results indicated a strong commonality factor between PTSD and depression. Of three indices of reward functioning (i.e., hedonic pleasure, reward motivation, and environmental reward availability), environmental reward availability alone was related to unique latent factors for PTSD and depression, and their commonality. Findings suggest that environmental context may be the key to understanding the role of reward in PTSD, depression, and psychopathology broadly.