Stanford is conducting a research study on cognitive outcome in breast cancer, and we need healthy woman to participate in looking at the differences between woman who have breast cancer and woman who do not. Some women have difficulties with certain cognitive functions following breast cancer chemotherapy including struggles with memory, attention, processing speed, multitasking and problem solving. The goal of this National Institutes of Health study is to improve our understanding regarding these difficulties and try to identify women who are at the most risk for having them. We need healthy controls to gain a better understanding of the effects of chemotherapy on the brain. We are looking for women who: • are healthy with no major medical conditions • are age 21-65 years • are free from any metallic implants or biomedical devices Participation involves: • Cognitive testing: you will be administered measures of, memory, attention and processing speed. This will require approximately 30 minutes of your time • Brain MRI scan: this involves lying in a semi-enclosed space for 30 minutes total while a machine takes images of your brain. There is no radiation or other harmful effects. • We will ask you to complete the cognitive testing and MRI scan three times: baseline, 18-22 weeks after baseline, 10-14 months after baseline Benefits of participation: • You will receive an honorarium of $100 for your participation after each study appointment ($50 for each cognitive testing session and $50 for each MRI scan). • We cannot guarantee that you will receive any specific benefits from participating. Potential risks of participation: • You may experience mild, temporary frustration and/or anxiety during difficult cognitive testing items and/or the MRI scan. To see if you qualify, please go to <a href= website</a>, or for further information please contact Clement Lee (650-308-9903). For further information regarding questions, concerns, or complaints about research, research related injury, and questions about the rights of research participants, please call (650) 723-5244 or call toll free 1-866-680-2906 or write the Administrative Panel on Human Subjects in Medical Research, Administrative Panels Office, Stanford University, Stanford, CA 94305-5401.