Concrete operations and attentional capacity

Abstract

In order to test predictions regarding the attentional capacity requirements of Piaget's stage of concrete operations, a battery of concrete operational tasks (class inclusion, transitivity of length and of weight, multiplication of classes, multiplication of relations) and two measures of attentional capacity (backward digit span and the Figural Intersection Test) were administered to 120 first, second, and third graders. With the exception of class inclusion, the results supported the hypothesis that three units of capacity would be necessary for solving each concrete operational task. Class inclusion was considerably casier than the other concrete operational tasks and was solved by nearly all children, a result which suggests that this version of the class inclusion task could possibly be solved without operational reasoning. The data also supported the prediction that transitivity of length and of weight, although differing in overall difficulty, would not differ in capacity demand. Instead, the horizontal decalage between length and weight was explained in terms of children's tendency to infer relative weight from relative size.