Five experiments tested hypothesis that the A-not-B error results from general processes that make goal-directed actions to remembered locations. Findings showed that 2-year-olds' performance on the A trial was accurate. When the object was hidden at Location B, searches after 10-second delay were biased in the direction of Location A. This bias…

Three experiments in which photo or video presentations could guide one's search for a hidden object showed that under certain circumstances even 24-month-olds displayed representational insight. The first two experiments replicated earlier findings of chance performance across 4 trials, with 24-month-olds performing above chance in 3 of 4…

Strategies young children used to correct errors in nesting seriated cups changed substantially with age, becoming increasingly more flexible and involving more extensive restructuring of the relationships among the cups. The same trend toward increasing flexibility of thought and action also appeared in procedures children used to combine the…

Examined in 2 studies the ability of 2- and 3-year-olds to learn to use tools via imitation. Found that when shown a correct solution to a tool-using task, all children managed at least a partial solution. When shown an incorrect followed by a correct solution, 2-year-olds produced a partial solution and most 3-year-olds produced a full solution.…

Examined word retrieval in 14- to 24-month-olds. Found that children with limited productive vocabularies were less likely to produce labels of hidden objects than children with larger vocabularies, even though all could name them and did well when asked to find them. Pictorial cues facilitated word retrieval. Naming errors peaked among children…