Memory development throughout the second year: overall developmental pattern, individual differences, and developmental trajectories.

The present three-wave longitudinal study analyzed the development of declarative memory in N=92 infants (12-, 18- and 24-month-olds) using a deferred imitation task. As expected, overall memory performance improved throughout the second year. Previous research is also replicated insofar as stability of inter-individual differences was low to moderate within this age range. In addition, cluster analyses identified two developmental groups showing different growth and different stability patterns. Multivariate analyses revealed specificities in language and self-development in these two developmental groups having different developmental trajectories.