Recent research shows that the time you’re asleep might be a great time to pick up a new skill. Listening to words in a language you’re trying to learn while you sleep can help you retain them, provided you originally learned them while awake. The same goes for learning an instrument – hearing a song in your sleep that you practiced while awake can help you remember how to play it. New things can be learned while sleeping; particularly, using smells. This tactic is used in helping people stop smoking, by associating cigarette smoke with an unpleasant odor.