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Episodic memory allows people to remember life’s defining experiences, such as a college graduation or wedding, as well as less significant events, such as a summertime concert in the park. Perhaps this is the reason that more than a century of psychological work and decades of neuroscientific work have focused on revealing episodic memory’s underlying mecha-nisms. However, there is still an important question about memory that has received relatively little attention: What makes up an episode in episodic memory? In other words, how does dynamic, ongoing experience get transformed into mean-ingful units in long-term memory (LTM)? Although this question has not been addressed directly, insight may come from theories of event perception and segmentation. Event-segmentation theory (EST) proposes that continuous actions are parsed, or segmented, into events (Reynolds, Zacks, & Braver, 2007; Zacks, Speer, Swallow, Braver, & Reynolds, 2007). EST also suggests that the percep-tion and understanding of everyday experiences is mediated by a system that uses mental models to make predictions about how those experiences should unfold. Event models are pro-posed to be active representations that incorporate the percep-tual details of the current experience with semantic knowledge of similar past experiences, as long as the current experience is congruent with the active mental model (Zacks et al., 2007). When perceptual details become incongruent with the active model (e.g., when one activity is finished and another is begun), EST proposes that the event model is updated to accommodate these changes. The points at which these updates are proposed to occur are called event boundaries (Zacks, Tversky, & Iyer, 2001). Perhaps because mental models are also prominent in theo-ries of narrative comprehension (van Dijk & Kintsch, 1983), much of the evidence supporting EST has come from the narrative domain. Researchers have shown that spatial and temporal shifts in narratives tend to be identified as even