Did you know that humans are the only mammals on earth that can sleep late at will? No other creature has that ability. You will never find a man on earth who never dreamed in his sleep. Not only dreaming but also talking in sleep, walking these things also happen to us.
Do you know exactly what happens to us after we sleep? And why do we dream? Although I will not go into any discussion about dreams today. Another day I will discuss the idea in detail In-Sha-Allah. Today I will discuss sleep. Today I will try to explain rest in the language of science.
What is Sleep?
Sleep is a normal process of resting in mammals and birds when the conscious reaction is stagnant. Sleep is the time when we are not aware of our surroundings within twenty-four hours of the day. Animals also dream in this particular stage of sleep.
Classification of Sleep: First, there are two types of sleep: rapid eye movement (REM sleep) and non-REM.
Rapid eye movement (REM sleep)
One-fifth of the night is spent sleeping. During REM sleep, our brain stays awake, our muscles relax, our eyes move from side to side, and we dream.
Non-Rapid eye movement (Non-REM)
Our brain is inactive during this sleep, but the body can move. During this time, the hormones are released, and the fatigue of the day is removed, and the body becomes fresh again.
There are four levels of non-REM sleep.
1. Pre-sleep stage – muscles relax, heart rate decreases, body temperature decreases.
2. Light sleep – quickly wakes up at this stage; there is a natural awareness of the surroundings.
3. Slow Wave Sleep– Low blood pressure, at this stage, people go to sleep or talk.
4. Dark slow-wave sleep – rest does not want to break easily. There is no normal awareness of the surroundings when broken.
We sleep between REM and Non-REM at night, turning these stages around at least five times.
We dream more in the morning. At night we can wake up for a minute or two except for a couple of hours. We do not always remember it. These are what we remember if we are thinking, or if there is any other difficulty (such as if someone else is sniffing or if there is a noise outside, etc.).
How much sleep do we need?
It depends mainly on our age. Young children sleep seventeen hours a day. When they are a little older, they sleep eight or nine hours a night. Adults usually get seven to eight hours of sleep.
The same kind of sleep is needed when you are older. But they usually get a good night’s sleep for three to four hours on the first night. Then their sleep is quickly shattered—people at older age dreamless. People of the same period also have different sleep patterns. Most people sleep for seven or eight hours.
For a small number of people, only three hours of sleep is enough. It is not good to sleep at night for more than seven or eight hours regularly. The short time we stay awake during sleep seems to be a long time. So we think we didn’t get enough sleep.
Maybe you fall asleep again and again during the day. This often happens when you do not sleep well at night. If you get more sleep during the day despite getting enough sleep at night for two weeks, then there may be some other cause such as diabetes, thyroid, or viral infection.
What happens if you do not sleep?
Anxiety is normal if you do not sleep. Not sleeping for half a night will make you feel tired the next day, but it will not harm you physically or mentally.
But if you don’t sleep for several nights, you will see:
Always feeling tired, sleepy eyes during the day, difficulty concentrating, and difficulty making decisions, feeling bad, driving a car, or driving a machine.
Every year several accidents occur as a result of people falling asleep while driving. Lack of sleep increases our blood pressure, weight gain, and diabetes.
Are there animals that do not sleep?
All animals, even insects, must sleep. Even low-intelligence animals, whose brains are very small or not at all, need sleep. Of course, the nature of sleep in their case is different from that of humans or other mammals. These lower animals may become inactive for a while, or respond less to stimuli.
Studies on fruit files have shown that the human brain undergoes a variety of biochemical reactions during sleep, such as the fly insect’s brain.
Therefore, it can be said that as a result of evolution, all animals in the animal kingdom have now reached such a state that they need any form of sleep to survive.
These were our sleep issues in a nutshell, but there are other issues such as sleep diseases, insomnia, talking in sleep, etc. I will discuss these issues in another episode. Today, in the next chapter, I will discuss the sleep of animals, birds, and other mammals.