Maternal gesture use and language development in infant siblings of children with autism spectrum disorder.

Impairments in language and communication are an early-appearing feature of autism spectrum disorders (ASD), with delays in language and gesture evident as early as the first year of life. Research with typically developing populations highlights the importance of both infant and maternal gesture use in infants' early language development. The current study explores the gesture production of infants at risk for autism and their mothers at 12 months of age, and the association between these early maternal and infant gestures and between these early gestures and infants' language at 18 months. Gestures were scored from both a caregiver-infant interaction (both infants and mothers) and from a semi-structured task (infants only). Mothers of non-diagnosed high risk infant siblings gestured more frequently than mothers of low risk infants. Infant and maternal gesture use at 12 months was associated with infants' language scores at 18 months in both low risk and non-diagnosed high risk infants. These results demonstrate the impact of risk status on maternal behavior and the importance of considering the role of social and contextual factors on the language development of infants at risk for autism. Results from the subset of infants who meet preliminary criteria for ASD are also discussed.