It's not news that sleep is tied to learning—even a 90-minute nap can significantly help boost your brain power—but if you want to cement new knowledge in your brain, recent sleep research demonstrates that a good night's sleep shortly following your studies has a significant impact on your ability to retain information.
The study in question asked participants to memorize related word pairs (e.g., circus – clown) and unrelated word pairs (e.g., cactus – brick). Some participants learned the words at 9am, some at 9pm. The 9pm crowd went to sleep shortly after learning the words. The 9am crowd did not.
The results: Sleep made no difference when participants were asked to recall the related words, but when participants were asked to recall unrelated word pairs, the 9pm group—the group that slept right after learning—did significantly better. So where your brain already has a strong semantic roadmap for learning (as is the case with the related word pairs), sleep doesn't have a major effect. Where it's forming new connections, sleep makes all the difference.
Stick that in your mind pipe next time you need to do some serious cramming. Photo remixed from Muhammad Rehan.