Everyday environments, even small regions within reach, vary dramatically in terms of material composition. Adapting one's manual behavior to such transitions can be considered to be an important element of skilled action. To investigate the origins of this ability, we presented 8-month-olds (n=24) and 10-month-olds (n=24) hard or soft objects on…

Examines children's understanding of what variables and relations are important in problem structures, and their use of these variables and relations in problem solving. (HOD)

Discusses variables related to task performance in the solution of the water-level problem, where subjects were asked to indicate the water surface orientation in a tilted vessel. Subjects ages 7 to 15 years participated. Suggests that field effects and the kind of rules in use contribute to the differences in performance, which can be shown even…