Beyond initial encoding: Measures of the post-encoding status of memory traces predict long-term recall during infancy

The first years of life are witness to rapid changes in long-term recall ability. In the current research we contributed to an explanation of the changes by testing the absolute and relative contributions to long-term recall of encoding and post-encoding processes. Using elicited imitation, we sampled the status of 16-, 20-, and 24-month-old infants’ memory representations at various time points after experience of events. In Experiment 1, infants were tested immediately, 1 week after encoding, and again after 1 month. The measure of 1-week trace status was a unique predictor of 1-month delayed recall. In Experiment 2, infants were tested immediately, 15 min, 48 h, and 2 weeks after encoding and again 1 month later. The measures of 15-min and 48-h trace strength contributed unique variance in 1-month delayed recall. The findings highlight the need to consider post-encoding processes in explanations of variability in long-term memory during infancy.

► We tested the contribution of encoding and post-encoding processes to recall in infancy.
► The status of 16–24-month-olds’ memory representations were tested at several time points.
► Alone, measures of encoding and post-encoding trace status predicted long-term recall.
► In combination, only measures of post-encoding trace status predicted long-term recall.
► Implications for explanations of causes of variability in long-term recall discussed.