The science on mind games may be inconclusive, but research seems to suggest that they can't hurt -- except possibly your wallet.

At Marbles: The Brain Store, shoppers can browse products that claim to exercise the brain. Most fall in the $10 to $50 range, though the store also offers "brain training" software programs for about $400.

The brain-fitness industry is flourishing as baby boomers look for ways to fend off dementia. Software products alone generated $295 million in 2009, up 35 percent from the previous year, according to SharpBrains, a San Francisco-based market research firm.

The Chicago-based Marbles operates three stores in Minnesota: Eden Prairie Center, Rosedale and the Mall of America. The stores don't exclusively target older folks; most customers in the Eden Prairie store are families with kids, but its founders were inspired by the idea of helping keep aging minds strong.

Some experts contend that playing games, solving puzzles or tackling other challenging or novel mental pursuits -- like learning a foreign language -- exercise the brain the way lifting a heavy weight exercises a muscle.

"We're not claiming to cure Alzheimer's or anything, but I feel confident in the science that if you stimulate your brain, you can show improvement," Marbles CEO Lindsay Gaskins told the Chicago Tribune. "No one is going to say it's a bad idea to exercise your brain."

It's unclear whether that's better accomplished by exercising your mind or -- as one former Marbles employee said she's planning to do -- by learning to tango.