SV2A in Older Adults

Inclusion Criteria: * Able to provide informed consent * Male or female, aged ≥50 years * No history of significant medical or neurological disease * BMI ≤ 50 * If woman of childbearing potential, must agree to use an acceptable method of birth control, as determined by the principal investigator, for the duration of the study and up to one month after completion of PET scans Exclusion Criteria: * Women with a positive pregnancy test or women who are lactating * Have had exposure to ionizing radiation that in combination with the study tracer would result in a cumulative exposure that exceeds recommended exposure limits; * History of a bleeding disorder or are currently taking anticoagulants * Subjects who have donated blood within 8 weeks of the present study