Preschoolers optimize the timing of their conversational turns through flexible coordination of language comprehension and production

Conversation is the natural setting for language learning and use, and a key property of conversation is the smooth taking of turns. In adult conversations, delays between turns are minimal (typically 200ms or less), because listeners display a striking ability to predict what their partner will say, and formulate a response before their partner’s turn ends. Here, we test how this ability to coordinate comprehension and production develops in preschool children. In an interactive paradigm, one-hundred-and-six 3-to-5-year-olds (and forty-eight adults) responded to questions that varied in predictability, but were controlled for linguistic complexity. Using a novel distributional approach to data analysis, we show that when children can predict a question’s ending, they leave shorter gaps before responding, suggesting that they, like adults, can optimize the timing of their conversational turns. In line with a recent ethological theory of turn-taking, this early competency helps explain how conversational contexts support language development.