The current study examined how individuals with neurodevelopmental disorders navigate the complexities of learning within multidimensional environments marked by uncertain dimension values and without explicit guidance. Participants engaged in a game-like complex reinforcement learning task in which the stimuli dimension determining reward…

The Ravens Standard Progressive Matrices Test was administered to 48 subjects who then performed a card-sorting task under single- and competing-task conditions. Hick's Law and the Roth-Jensen procedure were used in task development. Complexity should have a more central role in speed of processing models of intelligence than ability to divide…

Item components that might contribute to the difficulty of items on the Raven Colored Progressive Matrices (CPM) and the Standard Progressive Matrices (SPM) were studied. Subjects providing responses to CPM items were 269 children aged 2 years 9 months to 11 years 8 months, most of whom were referred for testing as potentially gifted. A second…