Stress induced by negative feedback is known to impair recognition memory, although little is known about its neural correlates. Immediately before an auditory recognition test, a negative- and positive-feedback group received different, faked scores about their performance in a Tower-of-Hanoi task. Negative feedback increased reaction times for correct rejections of new sounds. Although the positive-feedback group showed frontally and parietally more positive-going event-related potentials for correctly recognized old items than correct rejections (OLD/NEW effect) between 400 and 700 ms, suggesting the presence of familiarity and recollection-related recognition processes, the negative-feedback group showed late (>1100 ms) sustained right-frontal OLD/NEW effects possibly reflecting postmemory monitoring. Hence, negative feedback might change recognition memory by disabling recollection in favor of postmemory monitoring processes.