The autopsies looked for plaques and tangles in the brain, both known to be trademark signs of Alzheimer's disease. Plaques are an accumulation of a form of the protein amyloid, which occurs between nerve cells. Tangles are an accumulation of a different protein, called tau, which occurs inside nerve cells.http://ummid.com/news/2011/September/13.09.2011/high_cholestrol.htm