This was never a clinical trial and should never have been approved.

The purpose of this study is to use a functional MRI (fMRI) index to compare the brain activity of healthy volunteers to that of people with mild cognitive impairment (MCI) and Alzheimer's disease. The ultimate goal is to develop an early diagnostic tool for Alzheimer's disease.

The study hypotheses are:

1. The fMRI index will differentiate between Alzheimer's disease, non-Alzheimer's dementia, and healthy volunteers;
2. The fMRI index will distinguish participants with MCI who convert to Alzheimer's disease from those who convert to a non-Alzheimer's dementia and those who remain stable;
3. MCI participants with a lower fMRI index at baseline who convert will progress to Alzheimer's sooner than those with a higher fMRI index, and MCI participants with a faster rate of fMRI index decline who convert will have an earlier onset of Alzheimer's disease.

The onset of Alzheimer's disease is insidious and the boundary between normal aging and Alzheimer's disease is blurred. In order to prevent and treat Alzheimer's disease, the investigators must be able to mark its preclinical stage, before brain damage becomes irreversible. There is a substantial body of research dealing with predictive markers of Alzheimer's disease in individuals with mild cognitive impairment (MCI). Despite these advances, however, researchers have not had enough evidence to recommend specific techniques that mark preclinical Alzheimer's disease. This new functional MRI (fMRI) index may fill this gap.

Participants will have two visits, one for memory testing and neurological examination, and one for an MRI scan. Each visit will take approximately 1½ hours. For volunteers who wish to do so, all study procedures may be completed in a single visit. Participants with MCI will be followed annually.

The investigators are currently enrolling healthy volunteers, as well as individuals with MCI (memory loss that does not significantly affect normal daily activities), Alzheimer's disease, and frontotemporal dementia (includes primary progressive aphasia).

Inclusion Criteria:

• 60 years of age or older (50 years of age or older for frontotemporal dementia patients)
• Normal memory, mild cognitive impairment (memory loss that does not significantly affect normal daily activities), or clinical diagnosis of Alzheimer's disease or frontotemporal dementia (includes primary progressive aphasia)
• Right-handed
• General good physical health

Exclusion Criteria:

• History of stroke or neurological disease (other than Alzheimer's disease or frontotemporal dementia)
• Seizures or head injury with loss of consciousness within the last five years
• Ferrous (magnetic) or electronic implants (due to the magnet in the MRI scanner)
• Claustrophobia

• Alzheimer's, non-Alzheimer's dementia, and mild cognitive impairment (MCI) participants recruited from the Medical College of Wisconsin/Froedtert Hospital Memory Disorders Clinic
• MCI and healthy volunteers recruited from the community