Maternal speech to infants at 1 and 3 months of age

The goal of this study was to assess maternal speech and in relation to changes in infant social behavior occurring around the second month post birth. Sixty infants interacted with their mother at 1 and 3 months of age in a face-to-face context. At 3 months, infants gazed, smiled, and positively vocalized significantly more than at 1 month. These findings point to a transition in infant social behavior at around the second month post birth. In addition, maternal speech to infants increased between these times in both amount and complexity, possibly in response to an increase in infant social behavior. Maternal speech was related to infant positive vocalizing at 3 months, suggesting mothers especially monitored infant vocalizing at 3 months. Individual differences in maternal speech were stable across visits.