2004 New Investigator Research Grant

A large effort in Alzheimer’s disease research is to identify and validate new diagnostic measures that would enable physicians to make a diagnosis early in the course of the disease. Early intervention may result in better treatment outcomes, particularly if new, more effective drugs become available.

Michael Greicius, M.D., M.P.H., and colleagues are investigating the potential of a relatively new form of functional magnetic resonance imaging (fMRI) to identify changes in brain activity that indicate the onset of Alzheimer’s disease pathology. The new strategy is intended to measure functional connectivity, or the effectiveness of cell-to-cell networking, among different brain regions affected by Alzheimer’s disease.

For this study, the investigators will conduct fMRI brain scans of people with mild Alzheimer’s disease, mild cognitive impairment (MCI), or no cognitive impairment. MCI, a disorder generally defined as a measurable decline in memory with no other dementia symptoms, may be an early indication of Alzheimer’s or a risk factor for developing the disease. The participants with MCI will receive a series of fMRI scans over time.

The researchers will assess the fMRI data to determine whether (1) there is an “average” measure of functional connectivity among specific brain regions in healthy older adults, (2) functional connectivity “scores” reliably distinguish between people with mild Alzheimer’s disease and those with no cognitive impairment and (3) abnormal scores in people with MCI indicate an eventual progression to Alzheimer’s. This study may lay the groundwork for larger investigations to assess the validity of fMRI measurement of functional connectivity as a valid diagnostic tool.