Accessibility and availability of actions and spatial displacements in memory for real-world events

When recalling the unfolding of real-world events, people do not represent the continuous flow of their previous experience, but rather a succession of key moments, while other moments are omitted. The extent of these omissions depends on the type of event recalled; for example, the course of actions is recalled at a better resolution than spatial displacements. It remains unclear, however, whether omissions in event recall reflect gaps in encoding, or whether the corresponding moments are available in memory but not accessed during retrieval. To address this issue, the present study assessed recognition memory performance for segments that were recalled versus omitted during the mental replay of real-world events involving actions and spatial displacements. Participants went on a tour on their university campus, going to several places and performing different actions while their experience was recorded using eye-tracking glasses. Twenty-four hours later, they freely recalled the events and completed a recognition memory task, discriminating between 5-s video clips from their own tour and those from other participants. We found that segments of experience were less likely to be recalled if they happened during navigation than during more complex actions. This pattern was maintained in the recognition memory task, indicating that moments of navigation have both lower accessibility and lower availability than moments of goal-directed actions. In a second experiment, we replicated these results and tested whether showing participants their original fixation patterns—overlaid on the video clips during the recognition task—would improve performance, which was not the case. We also found that recognition memory performance was lower for unrecalled moments than for recalled moments but nevertheless above chance, indicating that omissions in the recall of events result from both encoding and retrieval processes. Overall, our results suggest that episodic memory is biased towards the encoding and the retrieval of our actions, at the expense of more passive segments of experience. We discuss the specific characteristics of event perception and memory reconstruction that may favor the recall of memory traces related to complex goal-directed activities over that of less active moments like simple navigation, and that could explain the omission of available traces in the recall of real-life events.