First, the bad news: according to this article, “resting your textbook near your dreaming head won’t do any good.” Wouldn’t that be great?
But now here’s the good news: “if you’re learning a foreign language, it may help to play recordings of the language while you sleep.”
This is what they found in a study in June published in a journal called Nature Neuroscience. People in the study tried to use diagrams to learn to play two simple melodies on a piano. After spending some time learning the melodies, they took a nap for 90 minutes. While they slept, one of the melodies was played for them. When they woke up, they could play that melody better than the one they didn’t listen to while sleeping.
“In other words, if you’re learning a foreign language, it may help to play recordings of the language while you sleep. If you need to memorize information presented in a classroom lecture, it might also help to record the lecture and play it quietly at night.”
You can also use smell to help you remember your lessons: “this same memory consolidation process can be triggered by smells, too. If you study a Spanish vocabulary list while sitting next to a rosemary plant, and then put the plant on your bedside table for the night, the smell of rosemary may influence your brain to spend more time strengthening the memories of the Spanish vocabulary than it otherwise would.”