Feeling rested after a night’s sleep isn’t only about the number of hours you spend in bed. It also depends on how deep and continuous you think your sleep was. Scientists are still figuring out what the brain does to give us that sense of a truly refreshing night.
Dreams Might Make Sleep Feel Deeper
A recent study from the IMT School for Advanced Studies in Lucca, published in PLOS Biology, suggests a surprising idea: vivid, immersive dreams could actually help us feel that our sleep was deeper, rather than breaking it up.
What We Used to Think About Deep Sleep
For many years, researchers described deep sleep as a time when the brain is almost switched off—slow brain waves, little activity, and low awareness. Dreaming, on the other hand, was linked to REM (Rapid Eye Movement) sleep and thought to be a kind of light awakening.
This created a puzzle. REM sleep shows strong brain activity, yet many people say it still feels like deep sleep.
How the Study Was Done
Scientists recorded brain activity from 44 healthy adults over four nights using high‑density EEG. The participants slept in a lab while their brain waves were measured. Over 1,000 times, they were gently awakened and asked what they had been experiencing just before waking, how deep they felt they had slept, and how sleepy they were.
Dreams and the Feeling of Depth
Even as the body’s need for sleep slowly faded, participants reported that their sleep felt deeper later in the night. This feeling matched an increase in how vivid and immersive their dreams were. The researchers think that rich dream experiences may keep the feeling of deep, restorative sleep alive, even when the brain is still somewhat active.
Dreams as Sleep Guardians
Teamwork in Sleep Research
The project was a joint effort between the IMT School, Scuola Superiore Sant'Anna in Pisa, and the Fondazione Gabriele Monasterio. Their new sleep lab brings together brain scientists and doctors to study how the brain and body work together during sleep. These early findings set the stage for future work on healthy sleep and sleep disorders.