Greater-Bay-Area Healthy Aging Brain Study (GHABS)

Inclusion Criteria: * This project intends to recruit men and women between the ages of 55 and 90. The inclusion criteria are as listed: * Age 55-90 years old (including 55 and 90 years old). However, people with autosomal dominant and other familial Alzheimer disease (FAD) are not limited by age. * The score of the Geriatric Depression Scale (GDS) is less than 6 points. * There is a caregiver who can maintain at least 10 hours of contact per week and can accompany volunteers to the test site for testing. * Visual and auditory acuity is sufficient for neuropsychological testing. (Including normal corrected vision and hearing) * Be in good health and are expected to be free of disease interference during the study. * Volunteers are not pregnant, lactating or have reproductive potential (that is, women must be two years after menopause or undergo sterilization surgery). * Willingness and ability to participate in longitudinal imaging studies. * A modified version of the Hachinski Ischemic scores less than or equal to 4. * Have completed grade 6 education or have good work experience (sufficient to rule out mental retardation). * Must be able to speak Mandarin fluently. * Willing to undergo multiple 3T MRI scans and at least two PET scans. * Agree to collect blood for genomic analysis (including GWAS sequencing and other analyses), AD risk and protective genes such as apolipoprotein E (APOE), klotho, etc., and biological sample storage. * Agree to collect blood for biomarker detection. * Agree to share genomic data and biomarker samples. Exclusion Criteria: * MRI brain scan screening reveals infection, infarction or other focal lesions or multiple lacunes or lacunes in key memory structures. * Any volunteers who do not meet the MRI scan requirements, including having a cardiac pacemaker, eyes, skin or metal fragments or foreign bodies in the body. * Severe depression, bipolar affective disorder described in DSM-IV in the past year. * Psychotic features, agitation or behavioral problems that may lead to difficulty complying with the protocol content in the past 3 months. * Currently using medication to treat obsessive-compulsive disorder or attention deficit disorder. * History of schizophrenia (meeting DSM-IV criteria). * History of alcohol or drug abuse or dependence within the past 2 years (metting DSM-IV criteria). * Any major systemic disease or unstable physical condition that may make longitudinal research difficult. * Clinically significant abnormalities of B12 or TFTs may interfere with the study, low B12 will be excluded. * Currently using certain psychoactive medications (e.g., certain antidepressants, neuro-depressants, chronic anxiolytics, or sedative-hypnotics). Currently using warfarin or other anticoagulants such as dabigatran, rivaroxaban, and apixaban (except lumbar puncture). * Use of prohibited drugs. * Simultaneously participating in other clinical studies involving neuropsychiatry.