Adult and 10- and 12-month olds participated in two experiments to determine reliance of infants on object-kind information in solving problems of object individuation. Findings converge with those of object-first hypothesis of developmental course of object individuation. Findings suggest that young infants may represent one concept as criteria…

This study compared the regulation of cognitive activity in 30 children (ages 15 to 95 months) with autism or mental retardation matched for global, verbal, and nonverbal developmental ages. Testing on tasks of object permanence indicated that the autistic children had a pervasive difficulty in maintenance set, made more perseverative errors, and…

Eight experiments were conducted to examine 3- and 3.5-month-old infants' responses to occlusion events. The results revealed two developments, one in infants' knowledge of when objects should and should not be occluded and the other in infants' ability to posit additional objects to make sense of events that would otherwise violate their…

Examined perception of object unity in partial occlusion in 72 infants. Recorded how long subjects looked at a display of complete and incomplete rods. In test and control conditions, infants looked longer at broken rods than at complete rods, suggesting that infants' cognitive, visual, or attentional skills may be insufficient to support…