Proceedings of the Annual Meeting of the Cognitive Science Society

A key aspect of theory of mind is the ability to reason about other people's desires. As adults, we know that desires and preferences are subjective and specific to the individual. However, research in cognitive development suggests that a significant conceptual shift occurs in desire-based reasoning between 14 and 18 months of age, allowing 18- but not 14- month-olds to understand that different people can have different preferences (Lucas et al., 2014; Ma & Xu 2011; Repacholi & Gopnik, 1997). The present research investigates the kind of evidence that is relevant for inducing this shift and whether younger infants can be trained to learn about the diversity of preferences. In Experiment 1, infants younger than 18 months of age were shown demonstrations in which two experimenters either liked the same objects as each other (in one training condition) or different objects (in another training condition). Following training, all infants were asked to share one of two foods with one of the experimenters – they could either share a food that the experimenter showed disgust towards (and the infants themselves liked) or a food that the experimenter showed happiness towards (and the infants themselves did not like). We found that infants who observed two different experimenters liking different objects during training later provided the experimenter with the food she liked, even if it was something they disliked themselves. However, when infants observed two experimenters liking the same objects, they later incorrectly shared the food that they themselves liked with the experimenter. Experiment 2 controlled for an alternative interpretation of these findings. Our results suggest that training allows infants to overturn an initial theory in the domain of Theory of Mind for a more advanced one.