Toddlers get the nod

This thesis presents three studies exploring how children and mothers use conventional head nodding and head shaking gestures in the child's first two and a half years of life. Study 1 examines children's comprehension of head gestures that convey agreement and disagreement, in an experimental context. Study 2 presents an analysis of mothers' head gesture production in interactions with their children in semi-structured play sessions. Study 3 examines children's head gesture production in these same interactions, and asks whether early head gesture use is associated with later language outcomes. Study 1 revealed that 24-month-olds, but not 18-month-olds, can use a bystander's head gestures to disambiguate an informant's correct and incorrect claims about object features, including their names and hiding locations. Developmental change in representational skills during this period appears to facilitate the child's comprehension of head gestures in this setting. In Study 2, mothers used head gestures for a wide range of communicative functions, often reflecting apparent socialization goals and the encouragement of language use. They more often used head nods than head shakes. Mothers