Amyloid Plaque and Tangle Imaging in Aging and Dementia

A total of 165 volunteers will be recruited for this 2-year study. Participants will receive a baseline clinical and imaging evaluation and one follow-up evaluation two years later. These evaluations will include clinical and neuropsychological assessments, structural MRI and/or PET scans. Additional scans and scanning procedures will be performed on a subset of participants and participant visits, including serotonin density levels.

Inclusion criteria

• Agreement to participate in a clinical and brain imaging study
• Age 30 years or older
• No significant cerebrovascular disease - modified Ischemic Score of ≤ 4
• For volunteers with MCI or dementia, there must be a family member or potential caregiver available
• Adequate visual and auditory acuity to allow neuropsychological testing
• Screening laboratory tests and ECG without significant abnormalities that might interfere with the study.

Exclusion criteria

• Evidence of neurologic or other physical illness that could produce cognitive deterioration; in addition to a physical and neurological examination, volunteers will be screened for Parkinson's disease
• History of myocardial infarction within the previous year or unstable cardiac disease
• Uncontrolled hypertension (systolic BP>170 or diastolic BP>100), history of significant liver disease, clinically significant pulmonary disease, diabetes, or cancer
• Major psychiatric disorders, such as bipolar disorder or schizophrenia
• Because medications can affect cognitive functioning, volunteers needing medicines that could influence psychometric test results will be excluded; use of any of the following drugs will also exclude volunteers: centrally active beta-blockers, narcotics, clonidine, anti-Parkinsonian medications, benzodiazepines, systemic corticosteroids, and medications with significant cholinergic or anticholinergic effects, anti-convulsants, or warfarin
• Current diagnosis or history of alcoholism or drug dependence
• Evidence of untreated depression as determined by a HAM-D (Hamilton, 1960) score of ≥ 12 (17-item version) or untreated anxiety by a score of ≥ 8 on the Hamilton Anxiety Scale (HAM-A; Hamilton, 1959)
• Use of any investigational drugs within the previous month or longer, depending on drug half-life
• Contraindication for MRI scan (e.g., metal in body, claustrophobia)