Depends on what you mean by "work". If you mean does it exercise your capacity to think about puzzles? Yes, it does. Will it endow you with knowledge? Not unless you are reading a book at the same time as playing a game. The pros are it keeps you sharp between the ears, giving you the ability to access your brain a bit quicker. The downside is you're not really learning anything. Reading a book will exercise your brain much better than any game.