Exploratory and play behaviors of infants reared in an institution and lower- and middle-class homes.
D002657:Child Development; D002668:Child Rearing; D002674:Child, Institutionalized; D005106:Exploratory Behavior; D005190:Family; D005260:Female; D006798:Housing; D006801:Humans; D007223:Infant; D007360:Intelligence; D008297:Male; D010988:Play and Playthings; D012919:Social Behavior; D012923:Social Class