The skill to recognize faces is integral to social interactions, but it is a skill that children with autism either fail to develop or lose early in life. They tend to focus on the mouth rather than eyes, missing cues to emotions and to facial identification. This young researcher, newly working in a renowned Yale autism laboratory, will study toddlers to try to answer questions of when, and why, face recognition deficits occur in this population. Ultimately, the findings may provide new ways to diagnose autism earlier, and might also lead to earlier behavioral interventions. Acquiring typical face processing skills depends on experience. Healthy newborns' face discrimination skills evolve during infancy into a more refined focus, initially on the hairline and ears, and eventually on the eyes and mouth. School-aged children with autism (aged four), however, show abnormal patterns in responding to faces. When do the abnormalities develop, and do they involve problems with motivation, attention, learning or memory? The researcher hypothesizes that toddlers with autism have an impaired ability, prior to age two, to process human faces. Further, this impairment is related to abnormalities in the way they scan the face, and to attention problems that interfere with remembering faces. This hypothesis will be tested in a total of 75 toddlers, aged 18 to 24 months. Using eye tracking technology, the investigator will compare toddlers with autism to typically developing and developmentally delayed toddlers, on their selective attention to faces, their skills in recognizing previously seen faces, and whether or not they scan the face typically (from eye to the mouth, with little interest in hairline or ears). Significance: The research may improve understanding of the role of face perception in the development of autism symptoms. Moreover, if the research identifies face recognition problems that are present before age two, the findings could lead to earlier identification of infants at high risk of developing autism, and initiation of new types of treatment begun in infancy.