The cause of infant categorization?

We asked whether infants are sensitive to causal relations between objects and outcomes and whether this sensitivity supports categorization. Fourteen- and 18-month-old infants were familiarized with objects from a novel category. For some, the objects caused an electronic toy to activate. For others, the objects were present during activation of the toy, but did not cause the event. For the remaining infants, the events were never activated. Infants were asked to select another category member from a pair of previously unseen objects (one from the familiar, and one from a novel, category). Infants were more likely to select the category match in the causal than the non-causal and no outcome conditions, suggesting that they capitalize on causal information in forming object categories.