Mother-Infant Contingent Vocalizations in 11 Countries.

Mother-infant vocal interactions serve multiple functions in child development, but it remains unclear whether key features of these interactions are community-common or community-specific. We examined rates, interrelations, and contingencies of vocal interactions in 684 mothers and their 5½-month-old infants in diverse communities in 11 countries (Argentina, Belgium, Brazil, Cameroon, France, Israel, Italy, Japan, Kenya, South Korea, and the United States). Rates of mothers' and infants' vocalizations varied widely across communities and were uncorrelated. However, collapsing the data across communities, we found that mothers' vocalizations to infants were contingent on the offset of the infants' nondistress vocalizing, infants' vocalizations were contingent on the offset of their mothers' vocalizing, and maternal and infant contingencies were significantly correlated. These findings point to the beginnings of dyadic conversational turn taking. Despite broad differences in the overall talkativeness of mothers and infants, maternal and infant contingent vocal responsiveness is found across communities, supporting essential functions of turn taking in early-childhood socialization.