Eight children from each of five age groups, 4, 5, 6, 7, and 8 years, were administered matrix tasks involving two nominal dimensions, color and shape. Nine stimulus cells and six attribute cells made up the apparatus. The attribute cells consisted of three colors and three geometric shapes; the stimulus cells made up a matrix consisting of the…

The differences in performance on a variety of cognitive measures were studied in 67 learning disabled (LD) and normal elementary school children. Younger and older Ss were administered tests of conceptual sorting, central and incidental learning, and selective attention. Teacher ratings of classroom hyperactive behavior were also examined. LD Ss…

Students in grades K, 1, 3, and 5 were administered the Rod and Frame Test (RFT), the Matching Familiar Figures (MFF) Test, and the Piagetian tasks of Discontinuous Quantity, Class Inclusion, Multiplication of Classes, and Multiplication of Relations. Cross-sectional trends were found in all tasks with older children being less impulsive, more…