Workouts for Your Brain

Afterward, nearly half of the Posit users noted improvements in everyday situations like remembering names or following conversations in a noisy restaurant, but so did 40% of the control group — and all they had to do during the study was watch the History Channel and get quizzed on it.

So what should we make of this? For starters, self-reporting is not a reliable way to assess how well our brains are working. And slick marketing makes it hard to tell what's good from what's gimmicky. "There is not enough evidence that paying for a $100 fitness program gets you better results than a free game of chess or learning a new card game or bridge strategy, when it comes to improving your memory," says P. Murali Doraiswamy, a professor of psychiatry and geriatrics at Duke University and head of the school's new mental-fitness lab. (See 10 myths about dieting.)

Doraiswamy is intrigued by many of the new brain-training products but dismayed by the lack of research on their effectiveness. "Manufacturers are putting the cart before the horse," he says. Ultimately, he wants his lab to be a testing ground for claims of enhanced cognition, a kind of Consumer Reports for brain-fitness products.

One well-documented way to slow memory decline is through plain old aerobic exercise, says Art Kramer, a cognitive neuroscientist at the University of Illinois, who found that six months of walking for about an hour three times a week improved memory, attention and decision making among study participants, whose average age was 72. "Physical activity appears to be neuroprotective," Kramer says. (See TIME's video about fitness gadgets.)

That helps explain why some consumers are hedging their bets by hopping on a NeuroActive Brain Bike. The $4,000 machine debuted a year ago at Lady of America fitness centers, where members — who tend to be older than the average gym rat — quickly fell for the cardio-cognitive combo. "Instead of mindlessly watching TV" while pedaling, says Gerry Weber, CEO of Lady of America, which has 300 women's-fitness franchises worldwide, "they're able to exercise their brain at the same time."

Perhaps what's most important to remember amid the thicket of memory games, iPhone apps and other newfangled gadgetry is to just do something — preferably something novel — that engages your brain. Oh, and make sure you enjoy it too. "If you hate going to the gym," notes Bill Thies, chief medical officer for the Alzheimer's Association, "you're not going to go there on a regular basis."

See the top 10 scientific discoveries of 2009.

Neurobic Activity: What's good and what's gimmicky

NeuroActive bike
It's well documented that exercise slows memory decline, so users will benefit from pedaling on this $4,000 bike. What's less clear is the effectiveness of the memory games, which riders play via wireless mouse

InSight Software
Posit Science's $395 program is designed to aid memory and speed up thinking. But only one InSight exercise has undergone extensive independent testing, which showed it improves driving safety

Brain Age Games
Patients at Duke's mental-fitness lab give high marks to these $20 game sets for Nintendo DS but find their improvement quickly plateaus in such activities as unscrambling letters or counting currency

Sudoku Puzzles
All you need to solve these number games is logic and a pencil. But since brain training requires both persistence and novelty, be sure to keep at it and also vary your regimen

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