A critical examination of two key aspects of Piaget's account of how small children come to understand basic number concepts. (Author/CS)

This study assessed the predictive utility of a classification-based model versus a representational memory-based model to account for the effects of verbal training on the acquired equivalence and distinctiveness paradigms. (Author/JMB)

One hundred and sixty subjects from five age levels ranging from 3 to 20 years compared photographs of dogs (e.g., two different Great Danes or a Great Dane and a Doberman pinscher) and judged whether they were similar or different. (Author/MP)

Two experiments examined six-month-olds' ability to form an abstract containment category. Results indicated that, after habituation to object pairs in a containment relation, infants looked reliably longer at an example of an unfamiliar versus familiar containment relation, indicating that they could form a categorical representation of…

Two experiments explored how infants learn to form an abstract categorical representation of support (i.e., on) when habituated to few (i.e., 2) or many (i.e., 6) examples of the relation. When habituated to 2 pairs of objects in a support relation, 14-month-olds, but not 10-month-olds, formed the abstract spatial category (i.e., generalized the…

Two studies examined whether infants' category discrimination in an object-examination task was based solely on an ad hoc analysis of perceptual similarities among the experimental stimuli. Findings indicated that 10- to 11-month- olds' responses varied systematically only with the presence of a category change, but not with the degree of…

Children often perseverate, repeating prior behaviors when inappropriate. This work tested the roles of verbal labels and stimulus novelty in such perseveration. Three-year-old children sorted cards by one rule and were then instructed to switch to a second rule. In a basic condition, cards had familiar shapes and colors and both rules were stated…