Two studies were conducted to examine whether the elderly maintain the competence to solve Piagetian conservation problems. The results are discussed in terms of a distinction between competence and performance. (JMB)

Conducted with fourth, eighth, and twelfth graders, this study was designed to extend investigation of the contradictory training paradigm of the O'Brien and Overton study (1980) to include performances with conditional syllogisms and to bring this effect to bear on the controversies of false positive and negative assessments at different ages.…

Focused on the developmental acquisition of the conditional implication interpretation of "if-then." Knowledge of three aspects of this interpretation was assessed for adults and 3rd-, 5th- and 8th-graders. Results showed the older three groups were significantly more likely to understand conditional implication, with improvement…

A study investigating developmental differences in the ability to reason with conditional propositions used five variations of Wason's selection task to assess conditional reasoning in 132 eighth, tenth, and twelfth grade adolescents. In addition to examining developmental differences, the study had as an objective to examine the role of semantic…

Several studies have shown that the elderly do not perform well on the Piagetian problems of logical thinking; the present set of studies aimed at demonstrating that the elderly maintain the competence to solve such problems. The first study performed by the authors assessed performance of 60 noninstitutionalized middle-class elderly females on…

Results are discussed in terms of the development and activation of cognitive structures. (Authors)

Third- and seventh-grade and college students were tested to assess developmental differences in improvement following contradiction training and to investigate whether improved performance transfers to other conditional reasoning tasks. Results showed age differences: college students improved and transferred performance, seventh graders…

Examines the development of the child's concepts of certainty and uncertainty within the context of concrete and propositional reasoning tasks. Subjects were first, third, and fifth graders. Findings support the position that reasoning about concrete certainty and uncertainty requires a different competence than that required for reasoning about…