Prediction for infantile mechanism of action
According to the simulation account theory, the motor commands used to predict the sensory consequences of our own actions are also used to predict others actions. In contrast, the rationality theory suggests that predictions of others actions are based on inborn, abstract rules. To address this controversy, the EU-funded PREDICTING INFANTS (Infants predicting own and others’ actions: the neurocognitive development of action prediction) project performed studies that tracked hand and eye movement in infants. In this context, 14-month-old infants were presented with short video clips of point-light display of a person walking towards an object prior to reaching and grasping it. Two-dimensional eye-tracking showed that infants looked at the target object before action completion, showing signs of predicting the observed action performed by another person. In a second study, researchers provided head movements as cues for predicting the goal of the observed action. In this study, infants observed an actor building a tower of rings while their gaze was recorded. When the actor’s head was visible, the prediction capacity of infants was slower, indicating that they use hand movements as their primary cue for predicting the goal of the observed actions. In an interaction study, six-month old infants observed an experimenter shifting his gaze from a central position to an object positioned left or right, and subsequently grasping the object. In compliance with other studies, no gaze following was observed at this young age but gaze contact with the experimenter slowed down the infants’ object pick up. Additional studies showed that infants relied both on visual and tactile information when initiating a reach, indicating that they rely on the same sensory streams. Researchers also observed that infants made use of vision for postural control alongside position sense information. Taken together, the PREDICTING INFANTS study provided important knowledge on how infants predict the goal of the action. Results bring researchers a step closer to comprehending whether predictions of own and others actions develop in synchrony during infancy.
Keywords
Action, PREDICTING INFANTS, infant, eye-tracking, head movement