Mental Processing Aspects of Two Formal Operational Tasks: A Developmental Investigation of a Quantitative Neo-Piagetian Model.

Combinatorial and implicative operations were studied with tasks which eliminated many complexities found in Piagetian tasks, but which did not alter the logical strategies required by Piaget's task. Task difficulty in relation to information-processing demands of tasks and processing capacities of subjects at three age levels (8.0-10.1 and 10.2-12.1 years, plus adults) was investigated. The model used provided accurate predictions of task difficulty. Subjects who passed tasks reduced to rudimentary logical prerequisites subsequently failed logically equivalent tasks when quantitative constraints due to number of task variables or perceptual factors exceeded their processing capacities, and transferred operations to a Piagetian task. (Author)