The discovery of “mirror neurons” offers the potential for imitation-based interventions and may help define subgroups within autism spectrum disorder (ASD) to aid in the search for biological causes of autism. Dr. Bolton's fellow will carry out two studies of imitation impairments. The first study will examine a sample of children who were followed from age two years to adolescence to determine if two-year-olds with ASD who do not imitate differ over time from children with ASD who show typical imitation abilities. The second study will attempt to establish whether adults and children with ASD show impairments in the automatic imitation of hand, mouth, or eye region movements. The relationship between imitative behaviors, the understanding of self and others, and real-life functioning will be explored.