The role of working memory capacity in the temporal compression of episodic memories: An individual differences approach

Abstract

Remembering past events usually takes less time than their actual duration—their unfolding is temporally compressed in episodic memory. The rate of temporal compression (i.e., the ratio of the actual duration of an event to the duration of its remembering) is not constant but varies between individuals and as a function of the structure of events (e.g., the frequency of event boundaries). However, the cognitive mechanisms underlying these variations remain poorly understood. Given its role in the encoding and retrieval of information in episodic memory, working memory (WM) capacity could be an important determinant of temporal compression rates. We tested this hypothesis in two experiments in which we asked participants to watch and then mentally replay short videos showing people engaged in daily life activities. We showed that temporal compression rates depend on an interplay between WM and the structure of the remembered events: individuals' WM capacity (assessed using complex span tasks) were negatively associated with temporal compression rates, but only when the remembered events contained few event boundaries (i.e., few sub-events). This suggests that the temporal compression of events in episodic memory emerges when some of the sub-events to be retained are too long to be fully represented in WM.