Here's a thought: what would you say if you found out that you were eighty years old, with Alzheimer's? You may think this is a silly question, except that if you ever do become eighty years old with Alzheimer's you may have forgotten the fifty-five years in between, so now is your one opportunity to prepare an answer.
So far, I've considered and rejected, "That's interesting. Might as well put me to sleep, since I'm not really here any more." It's probably a little too depressing for those on the receiving end, and besides, I'm not sure about the morality of requesting a lethal injection for yourself. Still, the point remains--if I'm perpetually my twenty-five-year-old self, over and over again, between age eighty and ninety-five, then when I'm eighty-one I'm not really there--I'm back here in the early 21st century--so no one is there. There is no eighty-six-year-old Max in that case, and since I'm not there anyway, why bother keeping the body?
The best alternate answer I've come up with is, "Oh. I'm very sorry for all the fuss and bother. How have you been recently? Anything on your mind? There must be some reason you stopped by to chat." Obviously I won't have the foggiest idea who it is that's come by to talk, and I may have to ask clarifying questions like, "I gather that Millie is your wife? And you're my son?" But if ELIZA could do it, why not me?
 ELIZA, of course, was the original computer therapist. As I recall the history, Joseph Weisenbaum in 1966 was working on natural language processing. He wrote a program which would take your statements ("I'm mad at my girlfriend") and playing around with the grammar to spit the same information back out as a question ("How do you feel about the fact that you're mad at your girlfriend?" or "How long have you been mad at your girlfriend?"). The program had no real understanding of what "I am mad" meant, but it it recognized that "mad" was a verb and that the opposite of "I" was "you," so it was able to play around with the sentence structure and insert the conventional Rogerian couch-therapist words in the right places ("Tell me about..."). To Weisenbaum's surprise, some people really took to the program, insisting that it had helped them with their problems and was actually intelligent. Most people, of course, would have quickly realized that ELIZA was monumentally stupid, but I guess some people really did just want to talk about their feelings and ELIZA did a good job for them, thus demonstrating that you don't necessarily have to have any understanding of what people are talking about to help them with certain kinds of problems. You see how this relates to Alzheimer's?
"The presentation or 'gift' of the Holy Ghost simply confers upon a man the right to receive at any time, when he is worthy of it and desires it, the power and light of truth of the Holy Ghost, although he may often be left to his own spirit and judgment." --Joseph F. Smith (manual, p. 69)
Be pretty if you are,
Be witty if you can,
But be cheerful if it kills you.