Concept-Based Word Learning in Human Infants.

Whether infants initially learn object labels by mapping them onto similarity-defining perceptual features or onto concepts of object kinds remains under debate. We addressed this question by attempting to teach infants words for behaviorally defined action roles. In a series of experiments, we found that 14-month-olds could rapidly learn a label for the role played by the chaser in a chasing scenario, even when the different instances of chasers did not share perceptual features. Furthermore, when infants could choose, they preferred to interpret a novel label as expressing the agent's role within the observed interaction rather than as being associated with the agent's appearance. These results demonstrate that infants can learn labels as easily (or even more easily) for concepts identified by abstract behavioral characteristics as for objects identified by perceptual features. Thus, at early stages of word learning, infants already expect that novel words express concepts.