The main goal of the study is to elucidate the perceptual processes that serve to bias toddlers with autism spectrum disorder (ASD) toward objects instead of toward people and their immediate environment and to determine what drives their unusual exploratory behaviors. The research will focus on the perceptual dimensions of contrast and motion in 18-24 month old toddlers that are exhibiting signs of ASD. The toddlers will be assessed to determine if those that have ASD are biased toward high-contrast stimuli and if they react more to certain kinds of motion. Tests will also be done to determine the effect that certain distracters have on the toddlers' behavior. By shedding light on the mechanisms that lead to deficits in attention to social stimuli in everyday situations in young children with ASD, the project's findings will inform interventions that aim to minimize the effects of such deficits over the first years of life. Furthermore, these findings could aid the design of early diagnostic measures for high-risk infant sibling populations or infants with emerging but unclear symptoms of ASD.