Deferred imitation by 6-and 9-month-old infants: More evidence for declarative memory

Deferred imitation has recently surfaced as a hallmark measure of nonverbal declarative memory. In two experiments, we examined the developmental orig ins of deferred imitation during early infancy. Six- and 9-month-old human infants observed an experimental Perform specific actions with multiple obj ects. The infants' ability to reproduce those actions was assessed followin g a 24-hr delay. With a single demonstration session, infants of both ages reproduced significantly more actions that had been demonstrated than contr ol actions that had riot. These findings challenge the view that memory dev elopment is characterized by the emergence of a fundamentally different, de clarative memory system later in development. We conclude that the rudiment s of declarative memory are present bq at least 6 months of age. (C) 1999 J ohn Wiley & Sons, Inc.