Training 3-year-olds in rule-based causal reasoning

Preschoolers' understanding of causal rules was examined using a marble and ramp apparatus operating in two distinct configurations. Experiment 1, con ducted with 32 3-year-olds and 16 4-year-olds, examined whether children co uld predict where a marble would emerge when given verbal rules indicating the marble's trajectory. Over two sessions, 4-year-olds made correct predic tions, irrespective of the apparatus's configuration, Three-year-olds, in c ontrast, were unable to alternate between rule sets and performed poorly wh en the marble rolled diagonally across the apparatus. In two additional exp eriments, with the ramp uncovered to reveal mechanical shunts and feedback given on each trial, the verbal rules were presented with (Experiment 2) or without pointing gestures (Experiment 3). Generalization was tested using the original protocol of Experiment 1. Older 3-year-olds in both experiment s benefited from training, and most continued to perform well when gestures , feedback, and visual access to the mechanism were eliminated. Of the youn ger 3-year-olds, only those exposed to rules with gestures showed any impro vement, and the improvement did not generalize. The results indicate that p roviding redundant non-verbal cues may facilitate preschoolers' use of comp lex rule systems, with poor generalization attributable to young children's dependence on cues to access the relevant rules.