People lie about the past. They may lie in order to avoid consequences, to facilitate social bonding, or to make sense of their knowledge and their experiences. These reasons closely parallel proposed functions of memory flexibility, and a handful of studies have shown that under certain conditions, fabricating past events can lead to false memories and beliefs. Little research, however, has specifically examined whether lying about the personal past can alter autobiographical memory. The present studies are an investigation of how fabricating past experiences influences autobiographical memory, and the role of self-enhancing biases in guiding this influence.

Across three studies, participants were prompted to compose written fabrications about a childhood event that was unlikely to have occurred. Specifically, they wrote stories were rich with perceptual and emotional detail and embellished with plausible false content. After a short delay, they were asked to disregard their fabrications and provide sincere memory reports. Results indicated that fabrications influenced the subsequent memory reports, especially when the fabrications were thematically self-enhancing. Study 2 was a replication of Study 1, with additional experimental conditions intended to disentangle the influence of emotional valence from the self-enhancing features of the events, and to address the possibility that changes in mood accounted for the observed patterns. Results indicated that neither event valence, nor mood, could explain the patterns observed in Studies 1 and 2. In a third and final study, participants first completed one of three possible self-reflection tasks, which varied in their self-affirming and self-threatening characteristics. Next, they completed a fabrication task and memory questionnaire, as in Studies 1 and 2. Results indicated that self-affirming reflections yielded patterns of memory distortion similar to Studies 1 and 2, while self-threatening reflections appeared to reverse that pattern--threatened participants were less likely to incorporate self-enhancing fabrications into memory, and more likely to incorporate self-diminishing fabrications. The findings are considered in the context of theoretical questions surrounding motivational influences on how people recall past events.