Dynamic music-induced emotions shape the episodic structure of memory

Human emotions ebb and flow across time. However, it is unclear how these fluctuations in emotion influence the organization of episodic memory. Here, we examine how emotion dynamics transform experiences into memorable events. Custom musical pieces and a dynamic emotion-tracking tool were developed to elicit and measure temporal fluctuations in emotions. We demonstrate novel evidence that memory is organized around emotional states. While listening to music, fluctuations in emotional valence regulate an underlying tension between ongoing memory integration versus separation. Whereas a large absolute or negative shift in valence helps segment memories into episodes, a positive emotional shift binds sequential representations together. Both discrete and dynamic shifts in music-evoked valence and arousal also enhance delayed item and temporal source memory for concurrent neutral items, signaling the beginning of new emotional events. Emotions thereby have the power to sculpt episodic memories, informing new therapeutic methods for assessing and restoring memory organization.