Two experiments used object-manipulation tasks to examine whether one- to two-year-olds form superordinate-like categories by attending to object parts. Findings indicated that 14- and 18-month-olds behaved systematically toward categories with different, but not matching, parts. Without part differences, none formed superordinate categories.…

Examines the issue of object sorting in early infancy. Forty-eight infants at 6, 9, and 12 months were presented with eight sets of small, manipulable objects. At six months, selective manipulation was absent; at nine months, 94 percent of the infants sequentially touched similar objects and at 12 months 100 percent did so. (Author/DB)

A MAIN PROBLEM ARISING IN THE STUDY OF CATEGORIZING BEHAVIOR IN PRESCHOOL CHILDREN BY MEANS OF SORTING PROCEDURES WAS THAT PERFORMANCE APPEARED TO BE VERY MUCH A FUNCTION OF THE CHILD'S COMPREHENSION OF THE PARTICULAR VERBAL INSTRUCTIONS EMPLOYED BY THE EXPERIMENTER IN PRESENTING THE TASK. THE SPECIFIC AIMS OF THE FIRST STUDY WERE TO INVESTIGATE…