Coordinating attention to people and objects in mother-infant and peer-infant interaction.

In a longitudinal study, infants 6-18 months of age were observed in their homes playing with their mothers and with peers. Of primary concern was how they coordinated their attention to people and objects. Observations were coded using a state-based scheme that included a state of coordinated joint engagement as well as states of person engagement, object engagement, onlooking, and passive joint engagement. All developmental trends observed were similar regardless of partner: person engagement declined with age, while coordinated joint engagement increased. Passive joint engagement, object engagement, and onlooking did not change with age. However, the absolute amount of some engagement states was affected by partner: both passive and coordinated joint engagement were much more likely when infants played with mothers. We conclude that mothers may indeed support or "scaffold" their infants' early attempts to embed objects in social interaction, but that as attentional capabilities develop even quite unskilled peers may be appropriate partners for the exercise of these capacities.