One of the biggest neuroscience discoveries of the past ten years is the fact that new neurons are born in the brain throughout our lives. In fact, 1,000 new cells are produced every day in the hippocampus, a brain structure involved in learning and memory. Now scientists are trying to figure out how we can maximize the benefits that these cells bring, potentially boosting brain power and slowing cognitive decline.

Most of the new cells born in the adult brain die within weeks. But according to new research, learning can help those cells survive. "Good learners retain more new cells than bad learners do," says Tracey Shors, a neuroscientist at Rutgers University who presented her work at the Society for Neurosciences conference in Atlanta this week. "Something about the learning process keeps these things from dying." The findings, based on research in rats, could help explain why people who stay mentally active later in life seem to experience a delay in cognitive decline.