Infants' ability to mentally track the orientation of an object during a hidden rotation was investigated (N = 28 in each experiment). A toy on a turntable was fully covered and then rotated 90°. When revealed, the toy had turned with the turntable (probable event), remained at its starting orientation (improbable event in Experiment 1), or…

Examines the ability of infants to track and anticipate the final orientation of an object. Subjects were infants ranging from an average of four months to eight months old. Three experiments, with the last one as control, were carried out. Concludes that infants show some rudimentary mental rotation from four months of age. (MOK)

Examined 5- to 12-year-olds' judgment regarding the behavior of balance scales and other levers whose arms varied in a causal or a noncausal variable. Results indicated age-related increases in correct judgments about the influence of physical features of objects at an earlier age than about spatial relations between objects. (MOK)