Attempts to replicate Inhelder-Piaget results showing that a formal operational thinker uses all 16 binary operations of truth-functional logic. Results of present study suggest that the quality and complexity of usage of operations (as opposed to quantity) increases with age. (DP)

Purpose of the study is to test Piaget's hypothesis of a parallel relationship between moral concepts and logical structures in human development. (Author)

Behavior of 60 second-grade boys tested on three tasks designed by Piaget and on two cognitive style tasks showed great variability in each child's responses. (WY)

Piaget's concept of socialized speech was reevaluated with the use of everyday preschool speech collected during free play on 174 boys and girls aged 2 to 5. (MS)

These results support Piaget's position that preoperational children respond to the perceptual lack of equality but not to the lack of conceptual equivalence in class-inclusion problems. (Authors)

An investigation was made of the structure of riddles, riddle content, and the function of riddling among children ages 5 to 14. Interaction data and 1195 items were taped and hand-recorded during riddle sessions with 101 children from kindergarten, second, fourth, fifth, seventh, and eighth grades. (MS)

Examines Piaget's suggestion that the emergence of formal operations during the adolescent years is tied increasingly to occupational specialization. The subjects were 123 college students from four different pairs of academic majors. (MP)

In this and a previous study, only 29 percent of the subjects of mean age 13.6 had attained the conception of conservation of volume, a finding at variance with Piaget's earlier results. (Authors/CB)

Considers methodological issues surrounding the Piaget-Huang controversy. A probability model, based on the difference between the expected and observed animistic and deanimistic responses is applied as an improved technique for the assessment of animism. (DP)

This study was undertaken to determine the relative contribution of age, sex, and three stimulus features (board shape, block arrangement, and block shape) to perceptual accuracy on 39 board/block adaptations of Piaget's three-mountain task. (Author/SB)

It was hypothesized that Piaget's argument on behalf of the reorganization of cognitive processes would gain empirical support from a color/form, matching similar objects problem for 52 6-year-olds from a variety of socioeconomic backgrounds. (Author/MS)

Nonoperational first graders were taught Piaget's horizontality concept. In comparison to control subjects, training group subjects significantly increased correct responses, maintained their gains, and transferred their training from a straight-sided jar to a round-sided jar. (Author/DB)

Analyzes third grade children's performance on the Mueller-Lyer Illusion for whole and partial presentations of the figure. Results do not support Piaget's theory of perceptual development but are consistent with the theory of simultaneous and successive syntheses. (Author/BH)

This study was designed to provide empirical support for viewing personality development from a cognitive framework. With controls established for IQ and socioeconomic status, 75 children between 6 and 15 years old were classified by level of cognitive functioning according to Piaget's system. (CS)