Tested the hypothesis that some attempts to reduce the performance demands of concrete Piagetian operational tasks may have allowed children to solve those tasks with preoperational functions. Administered two previously used versions of the transitivity task for length and weight to 120 children six- to nine-years-old. The second version was…

Investigated preschoolers' understanding of two distance principles: the direct-indirect and the same-plus principle. Children did better on tasks relevant to the principles than on principle-irrelevant tasks. Concluded that even young children conceive of distance as fixed intervals. (SKC)

Children and adults were tested on six speeded perceptual-motor and cognitive tasks, including a (1) response time task; (2) button tapping task; (3) pegboard task; (4) coding task; (5) picture matching task; and (6) mental addition task. Age-related change in processing time on most of these tasks was described by a single exponential function.…

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…