Joel Connelly at the PI.com, writing about longtime Seattle resident Ron Reagan's new book about his father, says Reagan believes his father showed signs of Alzheimer's disease during his presidency, and as early as 1981.

"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," Ron Reagan writes. "The question . . . of whether my father suffered from the beginning stages of Alzheimer's while in office more or less answers itself."

If the elder Reagan had known he was ill, he would have resigned the presidency, Ron Reagan argues.

"I've seen no evidence that my father (or anyone else) was aware of his medical condition while he was in office," says the book. "Had the diagnosis been made in, say, 1987, would he have stepped down? I believe he would have."

Ron Reagan makes reference to the first 1984 presidential debate, in which rambling answers by President Reagan raised - briefly - the age issue in his race against former Vice President Walter Mondale.

The younger Reagan's book, My Father at 100, comes out next Tuesday.