This is the only book that examines the theory and data on the development of implicit and explicit memory. It first describes the characteristics of implicit and explicit memory (including conscious recollection) and tasks used with adults to measure them. Next, it reviews the brain mechanisms thought to underlie implicit and explicit memory and the studies with amnesics that initially prompted the search for different neuroanatomically-based memory systems. Two chapters review the Jacksonian (first in, last out) principle and empirical evidence for the hierarchical appearance and dissolution of two memory systems in animal models (rats, nonhuman primates), children, and normal/amnesic adults. Two chapters examine memory tasks used with human infants and evidence of implicit and explicit memory during early infancy. Three final chapters consider structural and processing accounts of adult memory dissociations, their applicability to infant memory dissociations, and implications of infant data for current concepts of implicit and explicit memory. (Series B).