Probing reward function in posttraumatic stress disorder: Expectancy and satisfaction with monetary gains and losses

Background: Posttraumatic stress disorder (PTSD) may be associated with dysfunctional reward processing. The present study assessed for such dysfunction in both the expectancy and outcome phases of reward processing. Methods: Male Vietnam veterans with (n = 15) and without (n = 11) combat-related PTSD were administered a wheel of fortune-type gambling task. Self-reported ratings of expectancy and satisfaction were collected respectively before and after each experience of monetary gain or loss. Results: PTSD participants reported both lower expectancy of reward and lower satisfaction with reward when it was received. The latter result was manifest in a failure of PTSD participants to show the greater satisfaction that normally accompanies rewards received under conditions of low expectancy. Conclusion: These results suggest reward function impairment in PTSD related to expectancy, satisfaction, and the expectancy-satisfaction relationship.