Two studies with 9-, 11- and 13-month-old infants were conducted to investigate infants' ability to use an object's material properties to guide their object-directed actions. In study 1, 9- and 11-month-old infants played in an exploration phase with two objects made of different materials, one very heavy and the other one light and playable.…

Research on object exploration by infants addresses milestones in the process by normally developing infants, including spontaneous manipulation strategies. Implications for developmentalists working with high-risk preterm infants are noted, including the need for direct assistance in manipulation and for selection of materials. (CL)

Although a considerable amount is known about the development of object manipulation during the 1st year, less is known about how infants manually explore surfaces and relate objects to surfaces. To address these issues, 60 infants (20 each at 6, 8, and 10 months of age) were presented hard and soft objects on tabletop surfaces, which varied in…

Various counting tasks were presented to 24 congenitally, totally blind children, aged 3-13, to determine the behaviors employed to ensure accurate counting. Three dimensions of tactile strategies were found, including "scanning,""organizing," and "partitioning." A developmental progression in the ontogenesis of each…