Listen up! Speech is for thinking during infancy.

Infants' exposure to human speech within the first year promotes more than speech processing and language acquisition: new developmental evidence suggests that listening to speech shapes infants' fundamental cognitive and social capacities. Speech streamlines infants' learning, promotes the formation of object categories, signals communicative partners, highlights information in social interactions, and offers insight into the minds of others. These results, which challenge the claim that for infants, speech offers no special cognitive advantages, suggest a new synthesis. Far earlier than researchers had imagined, an intimate and powerful connection between human speech and cognition guides infant development, advancing infants' acquisition of fundamental psychological processes.