Weiner: And that's led some people to think, well maybe removing amyloid isn't going to give you a result, but there are other reasons. One possibility is that the drugs just didn't work very well. Another possibility is that if we waited until people are demented, it's too late.
Narrator: Weiner is the principle investigator of a national effort called the Alzheimer's Disease Neuroimaging Initiative, or ADNI. The primary goal of ADNI is to identify early biomarkers of the disease and its progression for both the diagnosis and the development of new treatments for Alzheimer's disease. For Science Today, I'm Larissa Branin.