Children's acquisition of tool use abilities is an important part of development but is not yet well understood. This study compares two modes of tool-use learning, observation and individual haptic experience. Two- and 3-year-olds had haptic experience with tools, observed tool use by others, had both haptic and observational experience, or no…

Recent studies suggest that 5-year-olds can add and compare large numerical quantities through approximate representations of number. However, the nature of this understanding and its susceptibility to environmental influences remain unclear. We examined whether children's early competence depends on the canonical problem format (i.e., arithmetic…

We compared the performance of twenty 5-7-year-olds on two spatial-temporal judgment tasks. In a semantic task, children located temporal distances from today that were described using conventional, temporal terms on a spatial timeline. In an autobiographical task, children judged temporal distances on the same spatial timeline for events that…

Developmental dyscalculia (DD) still lacks a generally accepted definition. A major problem is that the cognitive component processes contributing to arithmetic performance are still poorly defined. By a reanalysis of our previous event-related brain potential (ERP) data (Soltesz et al., 2007) here our objective was to identify and compare…

Fragile X syndrome is a common genetic disorder associated with executive function deficits and poor mathematics achievement. In the present study, we examined changes in math performance during the elementary and middle school years in girls with fragile X syndrome, changes in the working memory loads under which children could complete a…

This study examined the effect of emotional stimuli on 3- to 4-year old children's flexible rule use, as measured by the Dimensional Change Card Sort (DCCS). In Experiment 1, children in two countries (Canada and China) were given 2 versions of the DCCS. The Standard version required children to sort red and blue boats and rabbits first by shape…

We compared 1- and 2-year-old children's performance on Pretend and Reality tasks. Pretend tasks involved the comprehension of a pretend scenario, whereas Reality tasks did not. For example, the experimenter pretends to drink water from an empty cup, she fills another cup with imaginary water and then invites the child to drink. In the Reality…