Additional Study Information: The purpose of this study is to investigate (1) how the brain functions when it is performing specific cognitive tasks, and (2) how the brain systems supporting these tasks change as a function of aging. We are also investigating whether certain biological factors influence the course of age associated memory problems. By cognitive tasks, we mean tasks that involve perceiving, representing, or assessing things that are shown to us. If you are eligible, you will be asked to complete three visits: a Neuropsychological Assessment, and two fMRI scans. These scans allow us to infer which areas of your brain are more or less active while you are at rest or become more or less active as you perform specific cognitive tasks. You will be compensated a total of $300. In 5 years, you will be invited to return for a follow-up study.