Here's an interesting tidbit: Did you know that in their sleep, songbirds practice their songs? Or that rats who are in the process of learning a new maze do practice runs in their head while they doze? Recently, researchers recently built on those findings while trying to answer the question: Do humans learn in their sleep too?

Have you ever got a whiff of certain smell, only to have it trigger a memory long thought lost? Smell has long been known to be a powerful trigger for memory. During the study, researchers asked volunteers to play a Concentration-style memory game. During game play, some of the participants got a "whiff" of roses while others didn't. Later, they went to sleep inside MRI machines (eek!), and while they slept the same scent was piped in. The next day, the participants who had smelled the roses during play and during sleep played the Concentration game with 97.2% accuracy while the control group only got 86% correct.

The MRIs showed that when the scent of roses was piped in during slow-wave sleep (but interestingly, not REM sleep), a part of the brain that is linked to new learning was activated. It seems the smell triggered the brain to "learn" while sleeping. I'm not sure what this means for you and I in our day to day life, but I think that this research -- and really any research on sleep -- is fascinating. Do you?