Publications of Király, I.

Beyond rational imitation: Learning arbitrary means actions from communicative demonstrations

The principle of rationality has been invoked to explain that infants expect agents to perform the most efficient means action to attain a goal. It has also been demonstrated that infants take into account the efficiency of observed actions to achieve a goal outcome when deciding whether to re-enact a specific behavior or not. Puzzlingly, however, they also tend to imitate an apparently suboptimal unfamiliar action even when they can bring about the same outcome more efficiently by applying a more rational action alternative available to them. We propose that this apparently paradoxical behavior is explained by infants' interpretation of action demonstrations as communicative manifestations of novel and culturally relevant means actions to be acquired, and present empirical evidence supporting this proposal. In Experiment 1, we found that 14-month-old infants re-enacted novel arbitrary means actions only following a communicative demonstration. Experiment 2 showed that infants inclination to reproduce communicatively manifested novel actions is restricted to behaviors they can construe as goal-directed instrumental acts. The study also provides evidence that their re-enactment of the demonstrated novel actions reflects epistemic rather than purely social motives. We argue that ostensive communication enables infants to represent the teleological structure of novel actions even when the causal relations between means and end are cognitively opaque and apparently violate the efficiency expectation derived from the principle of rationality. This new account of imitative learning of novel means shows how the teleological stance and natural pedagogy – two separate cognitive adaptations to interpret instrumental vs. communicative actions – are integrated as a system for learning socially constituted instrumental knowledge in humans.

The early origins of goal attribution in infancy

We contrast two positions concerning the initial domain of actions that infants interpret as goal-directed. The [`]narrow scope' view holds that goal-attribution in 6- and 9-month-olds is restricted to highly familiar actions (such as grasping) ([Woodward et al., 2001]). The cue-based approach of the infant's [`]teleological stance' ( [Gergely and Csibra, 2003]), however, predicts that if the cues of equifinal variation of action and a salient action effect are present, young infants can attribute goals to a [`]wide scope' of entities including unfamiliar human actions and actions of novel objects lacking human features. It is argued that previous failures to show goal-attribution to unfamiliar actions were due to the absence of these cues. We report a modified replication of [Woodward, 1999] showing that when a salient action-effect is presented, even young infants can attribute a goal to an unfamiliar manual action. This study together with other recent experiments reviewed support the [`]wide scope' approach indicating that if the cues of goal-directedness are present even 6-month-olds attribute goals to unfamiliar actions.