Whether or not infants' earliest perception of the world is a "blooming, buzzing, confusion," it is not long before they come to perceive structure and order among the objects and events around them. At the core of this process, and cognitive development in general, is the ability to categorize--to group events, objects, or properties together--and to form mental representations, or concepts, that encapsulate the commonalities and structure of these categories. Categorization is the primary means of coding experience, underlying not only perceptual and reasoning processes, but also inductive...

Despite early speculations that young infants are unable to form memories, since the 1950s developmental scientists have documented amazing memory abilities in infancy and explored how these abilities develop. This research on memory development in infancy and early childhood has recently moved in exciting new directions. Extensions of work on memory systems in adults and the use of behavioral and neuroscience methods to study early developing memory abilities have lead to an explosion of ideas about the neural underpinnings of memory, its development, and the mechanisms involved in these...