New research breaks it down.

Some 2.3 million of U.S. adults over 65 – more than 4% – have a diagnosis of dementia. But even without a diagnosis, a certain amount of cognitive decline is normal as age sets in. And whether it’s ...

Connecting the dots: Far from being a mindless escape, video games help the brain process information more efficiently and adapt more readily to complex tasks, according to a growing body of research.