The role of reactivations during consolidation in the structure and accessibility of episodic autobiographical memories

Episodic autobiographical memory (EAM) relies on vivid encoding contexts, with the self as a central reference point. However, EAM models that account for both encoding and consolidation processes in naturalistic settings remain relatively sparse. This study investigated the impact of memory encoding and subsequent reactivations during the retention interval on EAM. Sixty participants incidentally encoded thirty events varying in emotional valence (positive, neutral, negative) and interaction type (action or observation), while navigating through a naturalistic virtual city. At the end of the encoding session, all participants rated each event on several subjective memory-related dimensions, including emotional valence, self-relevance, and anticipated rehearsal. One month later, they completed free recall and recognition tests. Additionally, a subgroup of thirty participants completed intermediate reactivations through free recall tests, administered immediately and one week after encoding. Between-groups analyses showed that one-month free recall performance was enhanced in the group with intermediate reactivations, whereas recognition performance did not differ, except for a significant increase in false recognitions in the reactivation group. Mixed-effects models based on the subjective encoding ratings identified two core predictors of long-lasting EAM, regardless of reactivation: event novelty and the richness of mental imagery. With intermediate reactivations, additional predictors emerged, such as emotional valence and prospective relevance of the event. Overall, this study contributes to predictive models of EAM by demonstrating how reactivations modulate memory consolidation in a naturalistic context, supporting a dynamic view of consolidation aligned with the Multiple-Trace and Trace-Transformation theories. These findings open new directions for ecologically valid memory research, with particular relevance for therapeutic and clinical applications.