Children with autism spectrum disorder (ASD) often have impaired communication, problems with social interaction, and repetitive and stereotyped patterns of behavior. While most research has attempted to treat the behavioral deficits commonly associated with ASD, few studies have attempted to improve the core features of this disorder. A recent study found that donepezil HCl helped to improve speech production, attention span, and ability to express emotions in a group of children with autism. This study will provide an opportunity to conduct further testing of the effects of donepezil HCl on the cognitive deficits presumed to underlie the core features of ASD.