This project will investigate the use of eye movements as a sensitive measure of language processing in young children with autism. Tracking eye movements is routinely used to measure comprehension in normally developing preverbal infants. The feasibility of using this method with preschool-aged autistic children will be evaluated using a series of experimental tasks to test the children's comprehension of various language structures (nouns, verbs, relational language, noun phrases, verb phrases, and word order). Performance on eye-tracking measures will be compared to standardized test scores to test the hypothesis that children with autism will show significantly greater comprehension of spoken language when tested using eye-movement measures than when evaluated on standard tests. Children will be invited to return six months after their initial testing to repeat the experiments and test the sensitivity of eye-tracking measures to developmental changes in language knowledge.