Research has revealed that the brain employs distinct circuitries that mediate positive, or rewarding, behaviors and negative, or aversive, ones. Post-traumatic stress disorder (PTSD) has long been thought to arise from overactivity in the negative valence system, however a new study shows that people with PTSD also displayed a deficit in activation of positive valence processing soon after the trauma, suggesting it plays a role in resilience to PTSD.