Maria Schönebeck, Birgit Elsner

• Infants in the second year of life not only detect the visible goals or end-states of other people's action, but they also seem to be able to infer others’ underlying intentions. The present study used event-related potentials (ERPs) to investigate the biological basis of infants’ processing of others’ goal-directed actions, with special regard to the involvement of bottom-up perceptual and top-down conceptual processes. In an adaptation of the behavioral re-enactment procedure, 14-month-olds were first familiarized with either full demonstrations (FD), failed attempts (FA), or arbitrary (AA) object-directed actions. Next, ERPs were measured while all infants saw the same two pictures of the end-states of the full demonstration (complete end-state) and the failed attempt (incomplete end-state). In the time-windows related to perceptual processing (100–200 ms after stimulus onset) and to conceptual processing (300–700 ms), ERP negativity over frontal and central regions was higher for the complete than for the incomplete end-state inInfants in the second year of life not only detect the visible goals or end-states of other people's action, but they also seem to be able to infer others’ underlying intentions. The present study used event-related potentials (ERPs) to investigate the biological basis of infants’ processing of others’ goal-directed actions, with special regard to the involvement of bottom-up perceptual and top-down conceptual processes. In an adaptation of the behavioral re-enactment procedure, 14-month-olds were first familiarized with either full demonstrations (FD), failed attempts (FA), or arbitrary (AA) object-directed actions. Next, ERPs were measured while all infants saw the same two pictures of the end-states of the full demonstration (complete end-state) and the failed attempt (incomplete end-state). In the time-windows related to perceptual processing (100–200 ms after stimulus onset) and to conceptual processing (300–700 ms), ERP negativity over frontal and central regions was higher for the complete than for the incomplete end-state in the FD and FA conditions. When comparing the FA and AA conditions, this pattern of results occurred only for the conceptual time domain. Moreover, beginning slow-wave activity (700–1000 ms) differed for the end-state pictures in the three conditions, suggesting differential encoding demands. Together, the electrophysiological data indicate that infants in the second year of life use bottom-up perceptual as well as top-down conceptual processing to give meaning to others' goal-directed actions.…