Sleep: the key to surviving final exam season

We often wonder whether it is better to review before going to sleep. Or is it better to reread your notes in the morning, right before the exam? That would keep the information fresh in our memory. In reality, science offers a clear answer to this question. When we are awake, "the information to be memorized is encoded within neocortical networks and hippocampal networks" [1]. Without these networks, it would be impossible for us to form new lasting memories, because they are the ones that work together to encode and store information.

The stages of sleep

Sleep is divided into four distinct stages, each playing a key role in the recovery of the body and the brain [2].

The first stage, falling asleep, marks the transition between wakefulness and sleep. Brain activity begins to slow, but it is still easy to wake up at this point. This stage does not bring much rest.

The second stage is light sleep. This is a sorting phase for information: the brain decides which recent data deserves to be kept in long-term memory and which should be forgotten. This process is essential to free up mental space and avoid cognitive overload.

The third stage is deep sleep. At this point, body temperature drops and awareness of the outside environment almost entirely disappears. This stage is crucial for the release of growth hormones as well as for the maintenance of bones and muscles.

Finally, the fourth stage is REM sleep, often considered a state close to a coma from a neurological standpoint. It is in this phase that the nervous system regenerates. "Our mental and physical recovery is optimized and moods are regulated", which makes it a valuable ally for managing exam-related stress and anxiety.

Sleep and memory consolidation

Each stage of sleep plays a role in consolidating what was learned during the day. Deep slow-wave sleep (stage 3) is particularly important for reactivating and strengthening memories: dates, facts and concepts are processed and recorded at that moment. That said, the different stages of sleep work together to ensure memory is consolidated effectively.

REM sleep, in particular, plays a crucial role in associating ideas, regulating emotions and stimulating creativity. That is precisely what can help you stay calm and find original solutions if an exam question throws you off.

In conclusion

The different stages of sleep occur at specific moments during the night and each serves a unique function. That is why full, uninterrupted sleep is essential. Going to bed too late or waking up too early can disrupt this cycle and harm learning. Reviewing late at night without a good night's sleep afterwards considerably reduces your chances of retaining the information well. So to maximize your performance, studying more is not enough — you also have to sleep better.

In short, sleeping well is just as essential as reviewing when it comes to succeeding on your exams. Good preparation is not only about piling up study hours, it is also about learning to study in a more effective and balanced way. Our tutors are there to help you understand more clearly, get organized and build confidence, so you can rest easy before the exam. 🌙✨

[1] Bertran, F., Harand, C., Doidy, F. & Rauchs, G. (2013). Rôle du sommeil dans la consolidation des souvenirs. Revue de neuropsychologie, 5(4), 273‑280.

[2]Les secrets des quatre phases du sommeil | National Geographic. (n.d.). https://www.nationalgeographic.fr/sciences/les-secrets-des-quatre-phases-du-sommeil