If you forgot to buy the paper when you were at the store this morning and had to go back to get one, that doesn't necessarily mean you're slipping. In fact, according to Dr. A. Mark Clarfield, chief of geriatrics, at Soroka Hospital and Sidonie Hecht professor of geriatrics at Ben-Gurion University of the Negev, what's happening is probably completely normal. "Memory is only one of the cognitive skills - that's the one that worries people a lot, and it's the one that's noticeable. But if you look at cognition more generally, it's intellect, memory, affect - how happy or unhappy you are - judgment, orientation and language. Those are the overall cognitive abilities that we worry about. People with Alzheimer's disease eventually have problems with all six." Just because you can't remember as well as you once did doesn't mean you're on the road to Alzheimer's, he says. "My son and I both play guitar. I know hundreds of songs. He's 18. When we learn a new song, he learns the words faster than I do, and I learn them slower than I used to. Does that mean I have Alzheimer's disease? I don't. With age, certain cognitive skills decline and some get better. Memory is one of those things - memory for faces, memory for names." Benign senescent forgetfulness is what science calls our inability to find our keys sometimes. "Where are my keys, not that I have keys," notes Clarfield. "Demented people don't know they have keys, or put them in an inappropriate place like the piano." He advises we "take a fairly relaxed view of the normal forgetfulness and problems that come, because if you're worried that 5 percent-10% of people over age 65 suffer from dementia, 85%-95% don't." His 18-year-old son has "practically nothing on his plate," Clarfield notes, while people his age (57) balance jobs, family concerns, financial worries, etc. - so it's not surprising they start to forget here and there. But can offerings like BrainSpa help us keep our edge? After reviewing its Web site and hearing what I'd done, Clarfield also likened it to "a membership in a gym, which my wife and daughter have and I don't, because I do my exercise without the gym, and they do it there. But we both do the exercises. The question is do the exercises make a difference, not the framework, and here I don't think we have evidence yet that the exercises necessarily will do anything for people who elicit the early signs of Alzheimer's. "Programs that promise the worried well that we have ways to prevent Alzheimer's disease or even imply that - that is premature, to be very polite." Clarfield takes issue with the passage on the Web site (www.brainspa.co.il) that says that "enlarging the brain reserve is by all research the best solution to the determined decline of aging," and Ronny Erez of BrainSpa's idea that adding new territory to the brain helps prevent the onset of dementia. "That's a hypothesis," he says. While it's true that more highly educated people tend to get less dementia - which would lead some to say if you educate yourself more, your risks will be reduced - there's another way of looking at it. "There's an alternative hypothesis that maybe higher educated people started off with a better brain, and were able to reach higher heights and got more brain reserve to start with. So nobody knows the answer yet to that dilemma, and on that hangs whether or not if you exercise your brain you can prevent or put off the disease. And that's why anybody who claims anything in this direction is selling a hypothesis, not a proof. "Are there ways not to forget your glasses, are there tricks, is it good to exercise your brain? The answer is yes, for many reasons not related to this. Can people teach you how to forget things less, play chess in old age? Yes. But the more important question is does this prevent disease, and there we can say unequivocally nobody knows yet." BrainSpa's group sessions are "a kind of zen of life and I won't say anything against that, but there's no evidence that that kind of discussion does anything to prevent the development of dementia or Alzheimer's later in life. Maybe it will, but we don't know yet." The diet consultation sounds good, "but what are they going to tell you that you don't know already - eat plenty of fruits and vegetables and not eat too much fat and not get fat," asks Clarfield. "I'd be curious to know what nutritional advice they have to improve the brain, because there isn't anything I know of that is convincing that you can prevent or put off brain disease by changing your diet, especially middle-aged to older people." So should we plunk down our money for this or similar ideas? "You're a consenting adult, and the question is, is there a downside to this? There's not much of a downside - they're not offering toxic drugs, they're not telling you to go bungee jumping. The downside is that if it doesn't work, it costs people money." However, he does warn about subjecting anyone who really has Alzheimer's to these types of games and exercises, since he says "they really can't handle it - it's like asking a heart patient to do more exercises than they can do." Overall, he found BrainSpa's claims "interesting hypotheses that remain to be proven... We don't have any proof either for or against such programs. It's premature... They seem to be professional, reasonable people. If you want to spend your money on that and not something else, fine. Will this prevent - and if you have early Alzheimer's, will this postpone - the evidence is not there yet. Who knows what will be in the future, but we can only work from what we know today." So what should we do if we keep forgetting where the damn remote control is? First of all, worry less. "What I ask people is: Do you drive from Jerusalem to Tel Aviv? And when they say yes, I say: 'That's what to worry about. It's dangerous.' But whether in another 20 or 30 years you're going to have Alzheimer's disease - there are other things to worry about before that. That's not to say that a patient who comes in with real problems that are not so benign has nothing to worry about. But I think what's important for the general public to know is that this is a common disease, but not everyone gets it." The good news is that Clarfield also told me about new evidence indicating that per capita, the amount of Alzheimer's disease is dropping, although not absolutely because the number of older people in the world is increasing. New links to a vascular component of the disease are a promising hypothesis, and he advises all middle-aged people to take their vascular risk factors seriously, if only to fight heart attacks and strokes.