Developmental changes in infants' and mothers' pathways to achieving joint attention episodes

Combining the joint attention approaches of Mundy and colleagues' (2007) experimental coding of infants' specific initiating and responding acts and of Bakeman and Adamson's (1986) descriptions of both infants' and mothers' behaviors during joint engagement, this study examined 29 infants' and mothers' initiatives and responses leading to success in achieving joint attention (JA) episodes during naturalistic interactions when infants were 13 and 17 months old. Analyses revealed developmental changes in initiative frequencies and in the origins of JA episodes. At 13 months, although infants' less sophisticated object-only initiatives (IObj) were most frequent, JA episodes most often originated in maternal combined initiatives (IJA), which focused on both object and partner. By 17 months, however, infants' combined initiatives were most frequent and led to more JA episodes than any other initiative type. Infants with more combined initiatives achieved more JA episodes at both ages and greater 17-month vocabularies.