The purpose of this study is to adapt measures of social and emotional cognition for valid use in neurodegenerative disease patients. The resulting battery of tests will be used to identify characteristic patterns of altered social functioning in different neurodegenerative diseases, measure specific symptoms found to improve early diagnosis of these disorders, and improve our knowledge of normal social and emotional cognition in healthy older adults. This project also aims to link any findings with structural neuroanatomy to improve our understanding of the neurologic foundations for social and emotional behavior.