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Napping puts the brain in a state ready for learning / Study confirms the active role of short sleep periods in the formation of neural connections

Even a short nap can help the brain recover and become more receptive to learning again. In a study published on January 22, 2026, in the journal NeuroImage, researchers from the Medical Center – University of Freiburg and the University of Geneva show that even a short nap is enough to reorganize connections between nerve cells in a way that allows new information to be stored more effectively. Until now, these effects were known to occur only after a full night’s sleep. The new study shows that a short nap can specifically relieve the brain and restore it to a state ready for learning—a process that could be particularly beneficial in situations requiring high performance.

“Our results show that even a short sleep phase can put the brain into a state where it can learn and absorb information more effectively again,” says study leader Prof. Dr. Christoph Nissen, who conducted the study during his time as Medical Director of the Sleep Laboratory at the Department of Psychiatry and Psychotherapy at the Medical Center – University of Freiburg. Today, he is a university professor and chief physician at the Department of Psychiatry, University and University Hospital of Geneva (HUG), Switzerland. 

What happens in the brain during an afternoon nap

The brain is constantly active during the day: new impressions, thoughts, and information are processed, strengthening the connections between nerve cells (synapses) in the process. These strengthened synaptic connections form an important neural basis for learning processes. However, they also lead to a kind of saturation, so that the brain’s ability to continue learning diminishes over time. Sleep helps to downregulate this excessive activity—without losing important information. “The study shows that this ‘synaptic reset’ begins after just one nap and that new information can subsequently be stored more effectively in the brain,” says Nissen.

“The study helps us understand how important even short periods of sleep are for mental recovery,” says Prof. Dr. Dr. Kai Spiegelhalder, head of the Section for Psychiatric Sleep Research and Sleep Medicine at the Department of Psychiatry and Psychotherapy at the Medical Center – University of Freiburg. “A short nap in between can help you think more clearly again and continue working with renewed focus.”

How the study was conducted

The study involved 20 healthy young adults who, on two afternoons, either took a nap or stayed awake. The nap lasted an average of 45 minutes. Since direct measurements of synapses in healthy individuals are not possible, the research team used established, non-invasive methods such as transcranial magnetic stimulation (TMS) and EEG measurements to draw conclusions about the strength and flexibility of the synapses.

The results showed that after the nap, average synaptic activity in the brain was reduced—a sign of sleep’s restorative effect. At the same time, the brain’s ability to form new connections was significantly improved. The brain was thus better prepared for new learning material than after an equally long period of wakefulness.

Practical Benefits and Outlook

The study provides a biological explanation for why people are often more productive after a nap. Especially in professions or activities that require a high level of mental or physical performance—such as in music, sports, or safety-critical fields—a short nap could be strategically used to maintain performance. “A nap can help maintain concentration and performance even under high stress,” says Nissen.

However, the researchers emphasize that occasional sleep problems do not automatically lead to a decline in performance. Particularly in cases of chronic insomnia, sleep-wake regulatory systems remain largely intact; rather, worries and poor sleep-wake habits dominate. In such situations, cognitive behavioral therapy for insomnia (CBT-I) is more appropriate than sleep aids, as the latter can disrupt the brain’s natural recovery processes and lead to the development of dependence.

Original title of the study: A nap can recalibrate homeostatic and associative synaptic plasticity in the human cortex
DOI: https://doi.org/10.1016/j.neuroimage.2026.121723
Link to the study: https://www.sciencedirect.com/science/article/pii/S1053811926000418