The role of action effects in infants' action control

In adults, the selection and the planning of actions are influenced by the anticipation of desired action effects. However, the role of action effects for action control in infants is still an unresolved issue. One important prerequisite for infants' action control is that infants are able to relate certain movements to certain effects. To test this assumption, it was investigated how infants' action control is affected by action effects. By applying an imitation paradigm, we studied 12- and 18-month-old infants who first observed an adult experimenter demonstrating a three-step action sequence on a toy bear. In three experimental groups, the second action step, the third action step, or no action step elicited an arbitrary sound as an additional acoustic action effect. It was coded how often each of the target actions was performed by the infant in a subsequent 90-s test phase. As predicted, the frequency of the infant's target action varied depending on which action step elicited the action effect. In both age groups, the target action that was combined with an acoustical effect was not only produced more often but also occurred with lower latency and was in most cases the first target action shown by the infants. These results are interpreted as evidence of the important role of action effects in infants' action control.