Reviews Greenough, Black, and Wallace's (1987) conceptual framework for understanding the effects of early experience and sensitive periods on development, and illustrates the applicability of their model with recent data on the consequences for animals and human infants of the acquistion of self-produced locomotion. (BN)

The developmental pattern of concurrent synaptogenesis in rhesus monkeys is consistent with a straightforward model of relations between brain and cognitive development. Concurrent synaptogenesis is hypothesized to lay the primary cortical foundation for a series of developmental levels in middle infancy that have been empirically documented in…