Sex-Specific Effects of Endocrine Disruption on Aging and Alzheimer's Disease

This study is examining how exposure to hormone-disrupting chemicals (substances in the environment that interfere with the body's hormones) might affect the risk of developing Alzheimer's disease differently in women compared to men, using brain imaging to track changes over time. **You may be eligible if...** - You are a woman aged 60 or older - You previously participated in this research study - It has been more than 6 months since you finished chemotherapy or had major surgery requiring general anesthesia - You are willing and able to give informed consent - (For the Jacksonville site) You identify as African American **You may NOT be eligible if...** - You cannot read or speak English - You are in hospice care - You are claustrophobic (especially for MRI and PET scans) - You have a heart condition called QT prolongation (if tau brain imaging is required) Talk to your doctor to see if this trial is right for you.