The feedback-related negativity (FRN) is an event-related potential thought to reflect a reward prediction error, when an outcome is worse than expected. Behavior motivated by the avoidance of negative outcomes is sustained through negative reinforcement processes. Escaping or avoiding a negative outcome may be successful or not, resulting in an analogous situation to that which elicits the FRN. We observed that when expected avoidance of an aversive outcome fails to occur, there occurs a negative deflection in the frontocentral event-related potential at approximately 350 ms, but with a slow wave following. We suggest that the FRN may be considered an index of a broader class of reward-based learning that also includes avoiding negative outcomes as well as expecting positive ones. © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins.