Most probably damage rather than a disease (like Alzheimer's).
I had saved an interesting article in my bookmarks about MRI and white matter damage when I was researching my vertigo/dizziness.
http://www.sciencedaily.com/releases...0415084520.htm
MRI pinpoints region of brain injury in some concussion patients
Date:April 15, 2014
Source:Radiological Society of North America
Look in
PubMed for the author Alhilali
e.g.
http://www.ncbi.nlm.nih.gov/pubmed/23781117
Radiology. 2013 Oct;269(1):249-57. doi: 10.1148/radiol.13122343. Epub 2013 Jun 18.
Symptomatic white matter changes in mild traumatic brain injury resemble pathologic features of early Alzheimer dementia.
Fakhran S1, Yaeger K, Alhilali L.