Hold on tight! Linking emotions and actions in the infant brain.

By the end of the first year, infants use others' emotions to interpret events, integrate social cues and build expectations on how people should behave (e.g., through social referencing). Yet, little is known about the neural correlates of linking others' emotions to their following actions. This priming study investigates 10-month-olds' electrophysiological (EEG) responses to happy and disgusted emotional displays toward novel objects (prime) and subsequent actions (pushing away or pulling closer the objects; target). Event-related potentials from 30 infants showed distinct neural markers associated with emotional processing of the prime, such as heightened early attentional response (Nc) and greater cognitive processing (Pc) in response to happiness over disgust. The target action of pushing away an object, especially following happiness, elicited increased slow wave activity, revealing working memory updating. Additionally, a significant mu-rhythm desynchronization, indicating motor resonance, was observed for the action of pulling objects closer when preceded by happiness. These findings indicate that by 10 months, infants attend to emotional cues and use these cues to form predictions about subsequent actions. These neural correlates of bridging emotions and actions before 12 months of life reveal, for the first time, early neural specialization for processing social cues in complex contexts.