Sleep and learning: why the brain keeps working at night

In short: Getting enough sleep helps to consolidate what you have learnt and prepares the brain to take in new information. Pulling an all-nighter before an exam therefore usually does more harm than good.

In more detail: During sleep, the day’s memories are reactivated and stabilised; experts call this memory consolidation. Deep sleep in particular is considered important for factual knowledge. The exact processes are still being researched, but the benefit of sleep for learning is well documented.

In detail

• Before learning: After too little sleep it is harder to concentrate and take in new information.
• After learning: Sleeping in the night after studying helps you retain what you have learnt.
• Sleep stages: Deep sleep and REM sleep alternate in cycles of about 90 minutes and probably serve different purposes (schlafzyklen-und-traumphasen).
• Avoid all-nighters: A night without sleep impairs attention, memory and mood on the day of the exam.
• Spaced rather than crammed: If you study over several days, you get several nights for consolidation (vergessenskurve-und-wiederholen).
• A short nap: A nap of about 20 minutes can improve alertness; naps that are too long or too late can disturb night-time sleep.
• A brief review in the evening: Going over the most important material again before bed is a sensible way to finish, but it does not replace studying over several days.
• Good sleep habits: Regular times, a dark, cool room and less screen time before going to sleep help (schlafhygiene-besser-schlafen).
• If there are problems: Persistent sleep problems should be checked by a GP.