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…

Five- to six-year-old children estimated the size of Euclidian objects using an addition rule of Height plus Width, rather than a multiplying rule. Within the framework of information integration theory, tested whether intensive handling of objects would facilitate shift from addition rule to multiplication rule. Found that following handling,…