Taking a nap is not only used to rest, it is also essential for the recovery of neurons in the brain, as neuroscience researchers demonstrate.
We know that sleep plays a central role in memory and learning, but the precise mechanisms at work in the brain remain actively studied. Recent research published in the scientific journal NeuroImage looked at a very concrete question: what happens in the brain when we take an afternoon nap? The authors start from a well-documented observation in neuroscience: the more the day progresses, the more brain activity strengthens the connections between neurons. Through overload, the brain eventually reaches a state of saturation, in which it becomes less receptive to new information and less effective at learning. This is where the nap would come into its own to fix it.
The objective of the study was therefore to measure whether a nap really helps to “reset” the brain on a biological level, and not just to provide a subjective sensation of rest. To do this, the researchers worked with twenty young, healthy adults who either took a nap or stayed awake for two afternoons. To observe what was actually happening in the brain, the researchers used painless methods that make it possible to measure its activity without damaging it. They were used to evaluate two essential things. First, the level of “overload” of the brain, that is to say the extent to which the connections between neurons were already very busy after several hours of waking. Then, they measured the brain’s ability to create or strengthen new connections, an essential process for learning and memorizing new information.
The results are clear and coherent on a neurobiological level: the nap which best restores these mechanisms lasts around 45 minutes. After this duration of nap, the researchers noted that the activity of the connections between neurons decreased slightly, a sign that the brain had been able to release the pressure accumulated during wakefulness. At the same time, the brain regained a better capacity to create new connections, which made it more available to learn, memorize or concentrate effectively.
In other words, after a nap of around 45 minutes, the brain is not only rested: it is objectively better able to form new connections and learn effectively. Conversely, staying awake for the same period maintained a state of synaptic saturation, less favorable to cognitive performance.
These results shed scientific light on the benefits of napping during the day, beyond preconceived ideas. It is not only a question of combating drowsiness, but of optimizing the functioning of the brain when it is subjected to prolonged mental load. The authors emphasize, however, that their observations concern young adults without sleep disorders, and that they do not replace the benefits of sufficient nighttime sleep. However, in a context of intellectual work, learning or prolonged concentration, a nap of around forty minutes appears to be an effective strategy to restore the brain’s real capacity for performance.
