Social orienting and initiated joint attention behaviors in 9 to 12 month old children with autism spectrum disorder: A family home movies study.

According to the Social Motivation model children with autism show deficits in social orienting (looking at faces and responding to name) at the end of their first year of life. In this model, those deficits are both the earliest behavioral consequences of an alteration in the dopamine reward system balance and the foundation of the social impairments that characterize this neurodevelopmental disorder. The current study tests two of the main predictions of this model: that social orienting deficits are the first behavioral manifestation of autism, and that they are developmentally related to joint attention deficits. We retrospectively analyzed family home movies of 9- to 12-month-old infants, 29 of whom were later diagnosed with autism and 16 of whom were typically developing. After confirming that the videotapes of both groups were similar in content of the scenes recorded (contexts, type of social activity, etc.), we compared their social orienting (social gaze and responding to name) and joint attention behaviors (gaze alternation and gestures). No significant differences between groups were found in looking at faces, but the group with autism showed deficits in responding to name and initiations of joint attention (IJA). Looking at people was not significantly correlated with IJA behaviors, but response to name was. The lack of group differences in looking at faces between 9 and 12 months, and the existence of IJA difficulties in the ASD group without concurrent impairment in looking at faces, do not support predictions of the Social Motivation model. LAY SUMMARY: Various theories have been proposed to explain the emergence of autism symptoms early in life. This study tested two key predictions of the Social Motivation model. Comparing family movies of children 9- to 12-months-old later diagnosed with autism or with typical development, we did not observe difficulties in looking at other people's faces but children with autism responded to name and used gaze and gestures to direct the adult's attention to events of interest less frequently. This absence of difficulties in looking at faces does not fit with what the Social Motivation model of autism predicts and therefore we must develop alternative explanations.