Mood During Consolidation Retroactively Biases Memory for Past Emotional Events

Mood-congruent memory (MCM) is a well-established phenomenon that occurs when emotional memory is biased towards content affectively congruent with a past or current mood. To date, however, a majority of research in this area has examined how mood directly impacts the encoding or retrieval of emotional memories, with comparatively less work examining the offline effects of mood during early consolidation. To address this gap in the literature, here we induced happy and sad moods after participants encoded emotional stimuli, and then tested memory at least a day later with both recall and recognition tests. Across multiple experiments using different stimuli, induction techniques, and memory tasks, we demonstrate that a change in post-encoding mood is associated with mood-congruent shifts in memory for the affective tone of an emotional experience, while also boosting recognition accuracy for mood-congruent stimuli. These effects were moderated by subjective arousal and self-relevance ratings of the stimuli at encoding, suggesting that phenomenological appraisals of a stimulus shape the influence of mood during consolidation. Our findings propose that MCM can arise from mood states dissociated from the initial encoding or subsequent retrieval of emotional material, such that mood retroactively facilitates MCM even after an emotional experience has already occurred.