Grant: Catalyst Grant: Pilot Projects in Aging

Alzheimer's Disease (AD) is often thought of as a disease that affects mostly the "gray matter" in the brain because the cells in the gray matter are the most damaged in AD. However, brain white matter is also very important part of the brain because the myelin in the white matter helps to speed up the communication between brain regions, and helps us to think more quickly and clearly. As people get older, some changes can happen to the brain white matter that scientists do not yet fully understand. We can see these changes on regular magnetic resonance imaging (MRI) scans because the damaged white matter looks very bright, and therefore they are called "White Matter Hyperintensities". Often, these hyperintensities appear to be related to poor blood supply. However, since most hyperintensities look pretty much the same on regular MRI, it is hard to distinguish between the ones that represent severe and moderate brain damage. In our laboratories, we have developed new kinds of MRI scans. These scans give us more information about what is causing different kinds of white matter hyperintensities. In our first studies using these methods, we found that even though hyperintensities could appear to be the same on regular MRI, they were not alike. In some cases, it looks as if there is damage to both the axon fibres and the myelin, but in others, it looks like there is only inflammation in the white matter. We now need to study more people who have Alzheimer's disease or who have normal memory so that we can see how well these methods will work in a larger group of subjects. This project will give clinicians new MRI tools and will help us understand some of the brain changes in Alzheimer's disease and in normal aging.