Early diagnosis of autism is key to ensuring the best possible outcome for children with the disorder because affected children who start intensive treatments young are known to fare better than those who do not. Dr. Nelson and his colleagues are looking for neural markers of the disorder that could be detected between 6 and 12 months of age, long before more noticeable differences emerge in the children's natural behavior. The study will use sophisticated neuroimaging tools to measure the brain's electric and metabolic activity, along with behavioral assays such as eye tracking. The researchers will use these tools to search for neural differences between high- and low-risk infants. The team will also track the development of language, social and cognitive measures in children from 6 months to 3 years old, to determine which of the markers observable between 6 and 12 months can predict an eventual autism diagnosis at 3 years.