According to one study, the human brain is experiencing short periods of awakeness, even during deep sleep, which are micro-tests that are too short to remember, but which have beneficial effects, especially on memory.
Hormone, like adrenaline.
A study published in Nature Neurososcience on July 7, 2022, under the leadership of neurologist Celia Kjerb of Copenhagen University, is not a phenomenon of insomnia, but a phenomenon of microtesting that occurs many times every night and is caused by noradrenalin, an adrenaline-like adrenaline adrenergic hormone, which also acts as a neuromediator that generates micro-incentives.
Celia Kjerb says she found that even in normal sleep, our brain wakes up more than a hundred times a night. It's important to know that the level of noradrenalin in the body is subject to wave change, rising and decreasing every thirty seconds. It's known as the oscillating amplitude. When the noradrenalin is many, the brain wakes up for a little while, and when the hormone is small, the brain sleeps.
For their research, scientists used mice. They put rodents in the brain with sensors, as well as microscopic optical fibers. This equipment made it possible to measure their brain activity accurately and continuously. Microtests are so short that the unsub can't remember them. However, according to science, it's a kind of awakening, although a sleeping person doesn't actually wake up every time.
In addition to the number of microtests every night, scientists found that mice with the most micro-tests had the best ability to remember. Before sleeping, rodents observed two different objects. When they woke up, one of the objects was replaced, and mice with the highest level of noradenalina were more likely to study the new subject. This proves that these mice remembered an object that was already present before bed.
According to researchers, mice have thus developed "supermemorials." It is possible that the dynamics of noradrenalina reinforce sleep processes that affect not only the memory of rodents, but also the memory of other mammals, including human beings.