Experience shapes functional connectivity during action observation in the first year of life.

Infants' action perception is connected to and affected by their own action experience. While the association between production and perception of action is robustly found in behavioral studies, less is known about the underlying neural mechanisms that are involved in this link. Recent findings suggest that infants exhibit heightened motor-visual connectivity when observing familiar actions, which scales with their level of action competence. However, it is still an open question whether experience and acquisition of a new action modulate motor visual connectivity. The period between 10-to-12 months is a transitional stage where infants become proficient in grasping while just beginning to develop the ability to point. In the current study, we asked whether 10-to-12 months infants exhibit motor-visual connectivity during observation of grasping and pointing actions, and whether motor-visual connectivity during pointing varies with exposure to an intervention that supports the development of pointing. We re-analyzed data including EEG recordings from 10-to-12-month-old infants during an action perception task, along with measures of their prior experience pointing and participation in a pointing intervention. We replicated previous findings of heightened motor-visual connectivity during the observation of others' grasping actions, but did not observe differences during the observation of pointing actions. Notably, we found preliminary evidence of an increase in frontal-motor-visual connectivity across the infant brain during the observation of pointing after a pointing intervention. Together, these findings suggest that different stages of action competence may be associated with distinct changes in the neural mechanisms underlying action perception, which are modulated by experience.