What is sleep?
Sleep is a natural state for humans. This is a physiological characteristic of a person. During sleep, a person relaxes, he rests.
The theory of the physiologist Pavlov states that in the process of any prolonged activity, the cells of the cerebral cortex begin to experience fatigue. As a result, the brain suspends their activity, resulting in sleep. In this way, a natural process of self-preservation from depletion of brain cells is carried out.
There are other assumptions and hypotheses about what sleep is and why it is needed. According to one of them, the state of sleep helps the brain process information received during the day. According to another, sleep is necessary to restore the general condition of the body. It is believed that the brain evaluates the body’s performance and looks for ways to restore it.
It is a proven fact that during sleep, the pulse, activity of the cerebral cortex, sweating, etc. decrease. On the other hand, metabolism increases during sleep.
Sleep phases
Sleep is a mysterious phenomenon that has interested humanity for more than one millennium. Research scientists have been studying the described state of the body for a long time. We managed to find out that sleep is a cyclical state. It is divided into phases: fast and slow.
As a result of the research, a device was developed with which it was possible to study sleep cycles. An electroencephalogram made with this device helped to obtain a visual image of how the phases of sleep change. The studies were conducted on sleeping people with sensors attached to their heads. During the experiment, a change in fast and slow oscillations was observed, which means a change in sleep cycles.
NREM sleep
The slow phase can be divided into 3 types:
- nap;
- shallow sleep;
- deep dream.
Drowsiness is characterized by a slowdown in the body's response to external irritants. This stage of slow-wave sleep helps a person in solving various problems. It is often during dozing that new ideas come to mind.
Shallow sleep is characterized by a decrease in the activity of the body as a whole: a decrease in body temperature, pulse, activity of the cerebral cortex, etc. But still, this stage of slow sleep is distinguished by sensitivity. At this moment, the body quickly reacts to external stimuli, which contributes to rapid awakening.
The deep stage of sleep is characterized by the process of restoration of the body, its regeneration. At this time, it is difficult to wake a person; he does not respond to external factors.
- 27-Feb-2021 Victoria: I dreamed that I was touching my teeth in my mouth with my tongue and they were spinning in all directions, right 360°. But they don't fall out. And even then they seem to be fixed normally in their places, but I am very worried about why they are spinning and I start twisting them with my tongue again. Then I start rinsing my mouth and spitting it out, not the teeth, but the stones. Round, different sizes, black (like stones, not teeth). I rinsed my mouth until nothing bothered me. And no matter how I didn’t see myself, I understood that my teeth remained with me.
- 11-Mar-2020 Alina: Hello! I dreamed that my brother accidentally hit me and I gradually began to spit out my teeth! First the root ones, and then the lower ones, she spat them all out, there were no lower ones left at all! It was a very unpleasant feeling! And then they inserted new ones into me, but they began to fall off! I don’t know what this is for... Please tell me
