In search of lost time: Reconstructing the unfolding of events from memory

Abstract

When remembering an event, not only do we recollect what happened, when and where it happened, but also how it unfolded over time. What aspects of events are encoded in memory to support this recollection? This question is central for understanding the nature of event memories and our reconstruction of the time passed. In this article, we investigate how the spontaneous encoding of unfamiliar animations during learning influences the recollection of how these animations unfold. Specifically, we examine two structural properties of dynamic event sequences known to modulate the amount of information encoded in memory: the perceived number of sub-events and their perceived similarity. We found that despite clock duration remaining constant, more sub-events and less similar ones led to longer recognition memory latencies, duration judgments and mental event replaying. In particular, across stimulus animations, both the perceived number of sub-events and their degree of similarity contributed to the prediction of duration judgments and the length of mental event reproductions. Results indicate that the number and nature of sub-events in a sequence modulate how we reconstruct its duration and temporal unfolding, thus suggesting that these event properties, which mediate the amount of information encoded for an event, modulate the subsequent recollection of its temporal unfolding.

Effects of learned episodic event structure on prospective duration judgments.

“…Less attention to the specific animation content was evidenced in relatively poor performance in recognition memory, compared with Experiment 1, and the absence of a condition effect in recognition times-an effect replicated several times when content is attended to (Faber & Gennari, 2015a, 2015b. Because our grouping conditions were based on the number of fine-grainedperceived as the smallest-segments and their similarity, which require attention to specific details of the animations (e.g., color or shape changes), the absence of a condition effect on duration ratings is not surprising, as these specific aspects may have not been attended to, encoded, or recollected.…”

“…The results of repeated measures ANOVAs with either subjects (F 1 ) or triads (F 2 ) as a random factor and recognition times as a dependent variable indicated that there was a significant main effect of condition on the response latencies, (Yonelinas, 2001), suggesting that properties of the events encoded in memory during the study phase were accessed or checked during memory judgments, with the conditions that required access to more segments and less similarity between them leading to increased response latencies. Because the implications of these recognition findings have been discussed in detail elsewhere, we do not discuss them further here (Faber & Gennari, 2015a).…”

“…trend across conditions so that as the number of segments increased, and the degree of similarity decreased, longer duration judgments should be observed (Faber & Gennari, 2015a).…”

The ebb and flow of experience determines the temporal structure of memory

“…Fluctuations in the rate of temporal signal drift may also relate to observations that event boundaries lead to exaggerated estimates of event sequence duration [50]. For instance, items appearing within the same scene context were remembered as ‘closer’ together than items spanning a scene change [27], even though the same amount of objective time had passed.…”

Neural pattern change during encoding of a narrative predicts retrospective duration estimates

“…In parallel, researchers in the domain of retrospective time estimation have shown that the degree of context change is a better predictor of duration judgments than alternative explanations, such as the number of items remembered from the interval (Block and Reed, 1978; Block, 1990, 1992). Indeed, changes in task processing (Block and Reed, 1978; Sahakyan and Smith, 2014), environmental context (Block, 1982), and emotions (Pollatos et al, 2014), as well as event boundaries (Poynter, 1983; Zakay et al, 1994; Faber and Gennari, 2015), lead to overestimation of past durations.…”