Educators often use concrete objects to help children understand mathematics concepts. However, findings on the effectiveness of concrete objects are mixed. The present study examined how two factors--perceptual richness and established knowledge of the objects--combine to influence children's counting performance. In two experiments, preschoolers…

Executive function mechanisms underpinning language-related effects on theory of mind understanding were examined in a sample of 165 preschoolers. Verbal labels were manipulated to identify relevant perspectives on an explicit false belief task. In Experiment 1 with 4-year-olds (N = 74), false belief reasoning was superior in the fully and…

Young children often exhibit flexible behaviors relying on different kinds of information in different situations. This flexibility has been traditionally attributed to conceptual knowledge. Reported research demonstrates that flexibility can be acquired implicitly and it does not require conceptual knowledge. In Experiment 1, 4- to 5-year-olds…

Subjects of 4, 5, 7, and 20 years of age performed a speeded classification task designed to isolate sources of interference in visual selective attention. While subjects of all ages were unable to avoid processing distractors, older subjects were better able to inhibit distractor processing. (RH)

Four experiments investigated 3-year-olds' understanding of the differential importance of shape for categorizing solid objects. Found that they categorized rigid and deformable objects differently in a non-naming task and knew that material was important for deformable items and shape for rigid items. In two naming tasks, they generalized names…