The behavioral development of rural Guatemalan infants was assessed shortly after birth on a Neonatal Assessment Scale (NAS) and at 6-, 15-, and 24-months-of-age on a Composite Infant Scale (CIS). Summary variables based on NAS performance poorly predicted later assessed performance even as recently as six months after birth. The CIS modestly…

Responds to Needham and Baillargeon's criticisms and offers an alternative resolution of the conflicting results between the laboratories regarding abilities of infants less than 12 months to use property/featural information for object individuation. Maintains that kind concepts are acquired as infants approach their first birthday and that…

Calls for a process-oriented approach to study of categorization in infancy. Maintains that further understanding of infant categorization and its changes with development requires a more direct assessment of infants' category formation. Argues that two research directions will enhance understanding of categorization: (1) contextual variations on…

This longitudinal study investigated the relationship of stress arising from medical problems of newborns to parent-infant interaction through the infant's first year. Significant interactive differences between full term and premature infants were found in feeding situations during the neonatal period and in floor play at eight months. The sample…