Sixty-four adults participated in a study examining the accuracy of metacognitive judgments during 28 hr of sleep deprivation (SD) and continuous cognitive work. Three tasks were studied (perceptual comparison, general knowledge, and mental addition), collectively spanning a range of cognitive abilities and levels of susceptibility to SD.…

Reports the use of a memory load-interference paradigm and the easy-to-hard paradigm as converging operations to study capacity limitations in five- to six-year-old's reasoning. Concludes that transitive inference ability in children is capacity limited. (HOD)

Conceptual analysis of two perspective-taking tasks identified a number of subtasks calling for equivalent operations of social reasoning within tasks of different content. Subtasks hypothetically formed a logical and developmental sequence of abilities required for decentering. The developmental significance of the hierarchy was tested among 121…