Event segmentation aligns emotional learning and episodic memory

Emotion prioritizes not only what was significant, but when it was significant. When temporal structure is insufficient to bind emotional relevance to distinct episodes, emotional experiences can lead to overgeneralization and source confusion. Here, we tested whether event boundaries serve as a control mechanism that allows emotional prioritization in memory to reset and re-bind as relevance changes over time. Participants completed a preregistered two-day Pavlovian category-conditioning in which category-shock associations reversed across multiple learning phases. In one group, each reversal phase was preceded by a brief but explicit event boundary signaling an associative transition; in the other group, reversals occurred continuously without an explicit boundary. Episodic recognition memory for trial-unique conditioned stimuli, tested 24-hours later, showed selective enhancement for threat-predictive items in the segmentation group—most prominently during early and final learning epochs—whereas continuous encoding produced flatter, less selective memory profiles that failed to fully track changing emotional contingencies. Individual differences in learning dynamics during encoding predicted selective episodic memory at 24hrs, with event segmentation shifting this learning-memory coupling to the most recent threat reversal rather than the earliest one. Overall, event boundaries promoted tighter alignment between episodic memory and emotional relevance at the time of experience. These findings suggest that event segmentation supports adaptive memory prioritization by binding emotional significance to what is most relevant in the moment.