Effects of Correct and Incorrect Demonstrations and Their Order on Causal Learning in 2-4-Year-Olds

Observing others' demonstrations is an important route through which children acquire causal knowledge and develop scientific thinking. Using the trap-tube paradigm, the present study investigated the effects of correct and incorrect demonstrations and their order on causal learning in 2-4-year-olds. Experiment 1 (N = 352) showed that 2-year-olds showed no evidence of causal learning across all demonstration types, and their performance did not differ significantly between conditions. Among 3-year-olds and 4-year-olds, performance was better overall in the mixed-demonstration conditions than in the single-demonstration conditions. Within mixed demonstrations, order affected only 3-year-olds, with better performance in the correct-then-incorrect condition than in the incorrect-then-correct condition. Experiment 2 (N = 365) showed that 2-year-olds did not differ significantly across demonstration types, and their performance was largely near chance, whereas 3-year-olds and 4-year-olds performed better in the mixed-demonstration conditions than in the consistent-demonstration conditions. All children were more likely to change the side of insertion in the mixed-demonstration conditions than in the consistent-demonstration conditions. Overall, the findings suggest that mixed demonstrations support causal learning from age 3 onward, whereas evidence in 2-year-olds was weak and inconsistent.