title: Age-related changes in children's use of external representations.
abstract: This study explored children's use of external representations. Experiment 1 focused on representations of self: Self-recognition was assessed by a mark test as a function of age (3 vs. 4 years), delay (5 s vs. 3 min), and media (photographs vs. drawings). Four-year-olds outperformed 3-year-olds; children performed better with photographs than drawings; and there was no effect of delay. In Experiment 2, 3- and 4-year-olds used a delayed video image to locate a sticker on themselves (self task) or a stuffed animal (other task). The 2 tasks were positively correlated with age and vocabulary partialed out. Experiment 3 used a search task to assess whether children have particular difficulty using external representations that conflict with their expectations: 3- and 4-year-olds were informed of an object's location verbally or through video: on half of the trials, this information conflicted with children's initial belief. Three-year-olds performed worse than 4-year-olds on conflict trials, indicating that assessments of self and other understanding may reflect children's ability to reason about conflicting external representations.
authors.affiliation: Department of Psychology, University of Toronto, Ontario, Canada. zelazo@psych.utoronto.ca
authors.forename: P D
authors.initials: PD
authors.lastname: Zelazo
authors.forename: J A
authors.initials: JA
authors.lastname: Sommerville
authors.forename: S
authors.initials: S
authors.lastname: Nichols
mesh_terms: D002657:Child Development; D002675:Child, Preschool; D003463:Cues; D005260:Female; D006801:Humans; D007389:Internal-External Control; D008297:Male; D012649:Self Concept; D014796:Visual Perception