The accessibility and availability of experience segments in memories for real-world events

When recalling the unfolding of naturalistic events, people do not represent the continuous flow of their previous experience, but rather a succession of discrete experience units—representing key moments of the past experience—that are separated by temporal gaps (i.e., some event segments are omitted). It remains unclear, however, whether these omitted segments have not been recorded in memory, or whether they are available in memory but not accessed at the time of retrieval. To address this issue, we assessed recognition memory performance for segments that were omitted when people recalled the event. Using a paradigm that allows the study of naturalistically encoded real-life events, we tested participants’ recall and recognition memory performances for the same event. Participants went on a 15-min walk on the university campus, while their experience was recorded using eye-tracking glasses. Twenty-four hours later they were asked to freely recall all the events they experienced during the walk and then received a recognition memory task constructed with the video footage obtained via the eyeglasses. More specifically, participants were asked to discriminate between 5-sec long videoclips obtained from their own walk vs from that of other participants, using a 6-point confidence scale. We then compared recognition performance for trials corresponding to moments that had previously been recalled and moments that had been omitted in recall. We found that performance for unrecalled moments was worse than for recalled moments but better than chance. This result indicates that omissions in the recall of events are an effect of different selective processes that occur both at encoding and retrieval.