How can an MRI help experts predict whether or not I have Alzheimer’s?

With an MRI, you can get a really detailed analysis of brain anatomy. We know that neurodegeneration or brain atrophy plays a big role in the path towards Alzheimer’s disease. We look for genetic signatures [groups of genes with unique characteristics] on the individual subject level and say, OK, does this anatomical profile fit into a set of other profiles that we’ve already learned about and does it indicate that this individual is at risk for Alzheimer’s disease?