Schedule of Events | Symposia

Memory for an event-scrambled story unscrambles over time

Poster Session C - Sunday, March 30, 2025, 5:00 – 7:00 pm EDT, Back Bay Ballroom/Republic Ballroom

William Fisher¹ (fishermwilliam@gmail.com), Andrée-Ann Cyr¹, Buddhika Bellana^1,2; ¹York University; Glendon Campus, ²Rotman Research Institute; Baycrest

Our memory for an event reflects a combination of both episodic and schematic contributions (Renoult et al., 2019), which change in different ways over time. Episodic details tend to be more susceptible to rapid forgetting than schematic details (Sacripante et al., 2022), and memories are often characterized as becoming less episodic and more schematic over time (Wiltgen & Silva, 2007). We propose a new and efficient experimental paradigm to quantify changes in episodic and schematic contributions to event memory over time. Participants read a short story with the order of events randomly scrambled. After a delay (0hr, 24hr, 48hr, 72hr, or 1-week), participants were asked to reorder brief descriptions of each story event from memory. If schematic contributions increase over time, the remembered order of events should increasingly reflect participants' understanding of how stories tend to unfold (i.e., schematic), rather than the order in which the events were presented (i.e., episodic). We computed two indices: (i) schematic signal -- Spearman correlation between the order of participants’ recalled events and the original order of events before scrambling; (ii) episodic signal – Spearman correlation between participant recall and the scrambled order in which the events were presented. We found: episodic signal decreased over time, in line with forgetting; schematic signal was above-chance at all delays; and schematic signal significantly increased over longer delays. Overall, when reading a scrambled sequence of events, human memory not only records, but increasingly unscrambles, event sequences over time – highlighting an intimate link between remembering and understanding.

Topic Area: LONG-TERM MEMORY: Episodic