Reexposure breeds recall: effects of experience on 9-month-olds' ordered recall

On the basis of three experiences, 9-month-olds recall specific events after one month. We tested whether multiple experiences are necessary, or merely facilitative, of 9-month-olds' long-term recall. In two experiments, using deferred imitation, infants were exposed to multi-step sequences either one time, two times, or three times prior to a one-month delay. In Experiment 1, regardless of the number of experiences, infants did not demonstrate recall. In Experiment 2, infants were tested on and reexposed to the events after one week; recall was tested again one month later. Performance after 1 week in Experiment 2 was greater than performance after one month in Experiment 1. Moreover, presumably as a function of reexposure after one week, infants recalled the individual actions of the events one month later. Infants in the three-experience condition also evidenced ordered recall after one month. Implications for the developmental status of the neural substrate supporting long-term recall are discussed.