Column: Brain-twisted or brain-washed -- can crossword puzzles and word games sharpen memory?

You wake up, pour a cup of coffee, and eventually make your way to one or more crossword puzzles, word games and other brain twisters. The test of banked knowledge and problem-solving ability can boost your ego, or deflate it. It's the "use it or lose it" theory in action, and as I get older, I'd like to believe these mental exercises can help keep my mind sharp and maybe even ward off memory loss, even if my wife usually beats me at all these games. But is there any science behind that, or is it wishful thinking? I am trying to solve that riddle, because since launching the Golden State column two months ago, I've heard from a lot of readers who -- like me --put at least a bit of faith in the value of mental gymnastics.