Ron Reagan Jr: Dad Was Showing Signs Of Alzheimer's While Still President

In his coming book, Ron Reagan Jr. says that his father was showing the early signs of Alzheimer's while still in office. Reagan Jr. says that he won't discuss the book until its release, but U.S. News & World Report today published several excerpts discussing the former president's state of mind while in office, closing with this paragraph from the book.

"I've seen no evidence that my father (or anyone else) was aware of his medical condition while he was in office. Had the diagnosis been made in, say 1987, would he have stepped down? I believe he would have. Far less was known about the disease then, of course, than is known now. Today we are aware that the physiological and neurological changes associated with Alzheimer's can be in evidence years, even decades, before identifiable symptoms arise. The question, then, of whether my father suffered from the beginning stages of Alzheimer's while in office more or less answers itself."