Alzheimer's Disease Neuroimaging Initiative Grand Opportunity

EMCI Inclusion Criteria: * Between 55 and 90 years of age * Study partner to accompany patient to all clinic visits for the duration of the protocol * Memory complaint by patient and/or study partner * Abnormal memory function score on Wechsler Memory Scale (adjusted for education) * Mini-Mental State Exam score between 24 and 30 (inclusive) * Clinical Dementia Rating = 0.5; Memory Box score at least 0.5 * General cognition and functional performance sufficiently preserved such that a diagnosis of Alzheimer's disease cannot be made by the site physician at the time of the screening visit * Stability of the following permitted medications for 4 weeks (unless stated otherwise): * Antidepressants lacking significant anticholinergic side effects * Estrogen replacement therapy * Gingko biloba is permissible, but discouraged * Washout from psychoactive medication (e.g., excluded antidepressants, neuroleptics, chronic anxiolytics or sedative hypnotics, etc.) for at least 4 weeks prior to screening * Cholinesterase inhibitors and memantine if stable for 12 weeks prior to screening * Geriatric Depression Scale less than 6 * Visual and auditory acuity adequate for neuropsychological testing * Good general health with no diseases expected to interfere with the study * Not pregnant, lactating, or of childbearing potential (i.e. women must be two years post-menopausal or surgically sterile) * Hachinski less than or equal to 4 * Six grade education or has a good work history (sufficient to exclude mental retardation) * Fluent in English or Spanish * Agrees to at least one lumbar puncture for the collection of CSF * Willing and able to complete all baseline assessments * Willing to undergo repeated MRIs and at least two PET scans and willing to provide DNA and plasma samples as specified * Willing and able to participate in a longitudinal imaging study Specific Inclusion Criteria for follow-up participants from ADNI1: * Must have been enrolled and followed in ADNI for at least one year diagnosed as either Mild Cognitive Impairment (MCI) or Cognitively Normal (CN) regardless of whether a diagnostic conversion has occurred since enrolling in ADNI * Willing and able to continue to participate in an ongoing longitudinal study; a reduced battery of tests can be requested from the project directors if the participant is not able/willing to complete the full battery * Study partner who has frequent contact with participant and can accompany participant to all clinic visits for the duration of the protocol Exclusion Criteria: * Any significant neurologic disease other than suspected incipient Alzheimer's disease, such as Parkinson's disease, multi-infarct dementia, Huntington's disease, normal pressure hydrocephalus, brain tumor, progressive supranuclear palsy, seizure disorder, subdural hematoma, multiple sclerosis, or history of significant head trauma followed by persistent neurologic defaults or known structural brain abnormalities * Screening/baseline MRI scans with evidence of infection, infarction, or other focal lesions; multiple lacunes or lacunes in a critical memory structure * Presence of pacemakers, aneurysm clips, artificial heart valves, ear implants, metal fragments or foreign objects in the eyes, skin or body * Major depression, bipolar disorder as described in DSM-IV within the past 1 year * Psychotic features, agitation or behavioral problems within the last 3 months which could lead to difficulty complying with the protocol * History of schizophrenia * History of alcohol or substance abuse or dependence within the past 2 years * Any significant systemic illness or unstable medical condition which could lead to difficulty complying with the protocol * Clinically significant abnormalities in B12, or TFTs that might interfere with the study * Residence in skilled nursing facility * Current use of specific psychoactive medications (e.g.,certain antidepressants, neuroleptics, chronic anxiolytics or sedative hypnotics, etc.); current use of warfarin (exclusionary for lumbar puncture) * Use of investigational agents one month prior to entry and for the duration of the trial * Participation in clinical studies involving neuropsychological measures being collected more than one time per year * Exclusion for amyloid imaging with 18F -AV-45: Current or recent participation in any procedures involving radioactive agents such that the total radiation dose exposure to the participant in any given year would exceed the limits of annual and total dose commitment set forth in the US Code of Federal Regulations (CFR) Title 21 Section 361.1 * Exceptions to these guidelines may be considered on a case-by-case basis at the discretion of the protocol director