This project will capitalize on the pilot grant that was funded in 2017 showing that brief, noninvasive, low-cost brain-based measures of learning in children and adults with deletion subtype of AS can complement and extend informant reports of adaptive functioning. Without the need for voluntary behavioral response, these measures are optimal across ages and levels of intellectual and communicative abilities. This project compared auditory evoked brain response potential (ERP) associated with language and learning and memory across individuals of different ages, focusing on the deletion genotype and then moving to other genotypes. A novel behavioral procedure (eye tracking) was used to objectively measure language understanding in persons with AS. Then the relationship was evaluated between these markers of speech and language processing and symptom severity, along with age-related differences. By documenting sensitivity of the objective measures to individual differences among persons with AS it will establish them as effective markers of cognition in AS, suitable for objective measurable biomarkers that could be translated into meaningful outcome measures.