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Reasons For Sleeping


Reasons For Sleeping

Almost a third of a person's life is spent sleeping. Could we have spent this time on something else or is sleeping just making life possible?

One of the first findings about sleep revealed that this state of reduced physical activity is not uniform, but that it consists of different phases whose number, names and divisions change to this day. And while many animals, as did their ancestors, sleep on branches surrounded by enemies and numerous dangers, today's man in his safe and pleasant environment is increasingly seeking medical help due to lack of sleep. Why is sleep important to us?

The enigmatic state of the brain

The most general division of sleep is into REM and non- REM phases, which, above all, differ in brain waves observed by electroencephalograms. Non - REM is divided into several phases, and the one characterized by slow brain waves is most often called deep sleep. The REM phase ( Rapid Eyes Movement ) is probably the strangest state of the brain, more mysterious even than sleep itself. The brain is as active as in awake people, and the muscles are at complete rest.

In this phase, he dreams the most, and the inactivity of the muscles prevents the body from reacting in accordance with what he dreams of, thus protecting him. In the 1950s, William Dement, one of the pioneers in sleep research, conducted the first systematic brain research in the phase named after rapid eye movements.

In the REM phase, the brain behaves similarly in all mammals, but its duration differs. This phase has also been observed in birds, although it lasts only a few seconds due to the conditions in which these animals sleep and the dangers to which they are exposed during that time. The number of minutes spent in the REM phase is not the same for all species, but in humans it also depends on the age in which it is located.

While babies spend up to eight hours in this phase, adults are in the REM sleep phase for a total of about an hour and a half, which makes a bigger difference between a baby and an adult than between a chimpanzee and a human when it comes to this trait. In adults, the most common term for the REM phase is early morning, which indicates the possibility of preparing the brain for wakefulness in this way.

In addition, the dreams that are characteristic of the REM phase are related to the processes that take place in the brain at that time and are important for abstraction and generalization. The REM phase is responsible for the creation of creative discoveries and the recognition of solutions, so the expression "leave the problem to sleep" has not only a metaphorical meaning .

Many writers, artists and scientists have said that ideas for their great achievements came about in a dream. Dreams provided them with inspiration, but also brought solutions to problems that they had long unsuccessfully sought in the waking state. Such experiences are not unknown to the average person, and the solutions do not come by chance, but processes that are important for learning, remembering and recognizing take place in the brain during sleep.

Organization of Memory

Francis Creek and Graham Michison studied the impact of the REM phase on memory and memory organization, and in one of their studies they examined whether sleep influences the emergence of new ideas. They divided the task with numbers to the respondents and explained the rules for solving it, but they did not tell them that there is an easier way to solve the task.

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After that, one group slept for eight hours, the other was awake all night, while the third group had eight hours of free time that they were not allowed to use for sleep. The most successful in solving the problem were the respondents who slept after receiving the task, and at the same time, in the largest percentage, they found an easier way to solve the task.

One of the researchers who has dedicated his career to finding the connection between sleep and learning is Robert Stikgold, a psychiatrist from Harvard. His research is responsible for the emergence of the term "Tetris effect", which names a well-known phenomenon - when during sleep before the eyes are images of activities that a person has been doing for a long time during the day. In 2000, Stikgold gathered a group of people who played tetris for three days and seven hours for research purposes.

Among them were those who played this game for the first time, as well as those who are well acquainted with it, but also people who had one form of amnesia and were not able to form new memories. Despite the differences in previous experience, their dreams were almost identical - everyone dreamed of Tetris, including those who did not remember ever playing this game.

After studying the "Tetris effect", Robert Stikgold conducted numerous other studies and concluded that sleep is very important for the formation of memory, but also that it is a selective mechanism that helps us to extract from our experience what we will remember and what will be transferred from short-term to long-term memory.

Why do we sleep?

The time spent sleeping is not lost, but it is what makes life possible. Many important processes take place in a dream, but it is not yet clear why and what the purpose of sleep is. Although at first glance it seems that reduced activity endangers life in nature and increases the chance of animals being attacked, this unconscious state has its advantages.

Some theories point out that sleep is a way to store energy and reduce its consumption at night when it is difficult to find food. According to other theories, sleep is necessary because then muscles and other tissues recover, and old or dead cells are replaced with new ones. Among the theories, there are those according to which sleep is closely related to changes in the structure and organization of the brain.

Sleep-like conditions can be seen in almost all living things, and the caenorhabditis elegans worm is the most primitive "sleeping" organism. However, not all species sleep the same. Some need more sleep than others, some animals sleep more times during the day, and there are differences in sleep quality.

Charles Nunn and David Samson, anthropologists at Duke University, have found a link between the time primates spend sleeping and their physical characteristics and the structure of the group in which they live. However, man is an exception. Based on the patterns observed in other primates, it is concluded that humans should sleep much longer.

The answer to the question why man sleeps the least of all primates lies in the quality of sleep. Namely, sleeping on the ground, and then in much better conditions, enabled a person to sleep safer and therefore better. While primates mostly sleep on branches and find it very difficult to reach the REM phase, humans are often in this phase, which accounts for about 25 percent of total sleep.

The amount and quality of sleep depends on the circadian rhythm, the internal clock that tells when it is time to sleep and when it is time to wake up. Biological processes are harmonized with the twenty-four-hour day, and in that way the organism prepares for the changes that take place in the environment on a daily basis. However, the circadian rhythm of people changes with age, so adults need less sleep than children, and recent research shows that teenagers go to bed late due to a specific internal clock.

The change of day and night leads to a change in body temperature and changes in the secretion of hormones, of which melatonin is the most important for sleep. Every night, the pineal gland begins to secrete more melatonin, and it changes the electrical rhythm of neurons, which the brain feels the need to sleep. In the morning, the secretion of this hormone decreases and the brain returns to the waking state. Every time we stay awake at night or change time zones, we fight against this natural cycle, and every exposure to artificial light confuses melatonin by sending it false information about the time of day.

Lack of sleep

During sleep, the level of cytokines increases, which leads to the strengthening of the immune system and the secretion of growth hormone, which is used to renew cells and tissues. In addition, sleep neutralizes neurotoxins, and the brain is cleansed of waste products, which was confirmed by research conducted in 2013 on mice by Miken Nedergard.

Rodents provided a lot of important knowledge about sleep, and experiments conducted by Alan Rechtchaven from the University of Chicago in the 1980s showed that life without sleep is impossible. The rats that participated in this experiment died after 32 days of sleep deprivation. Their death was interpreted in several ways, and the most common cause was a weakened immune system and brain damage.

Although it is not known whether something similar could happen to people due to lack of sleep, it is assumed that they can live longer without food than without sleep. The record of this kind was set in 1964 by 16-year-old Randy Gardner, who did not sleep for 11 days and 24 minutes and when serious changes in cognition and behavior were noticed.

It is known that CIA agents exposed enemies to insomnia, and the symptoms appeared after only three days. Blood pressure was getting higher, immunity was weakening, and metabolism was disturbed so that these people had an uncontrolled need for carbohydrates. Almost all of them had hallucinations, and their ability to think and make decisions significantly decreased. The surprising fact is that just a few hours of sleep was enough to get everything back to normal.

Although lack of sleep leads to serious consequences, the first research on sleep disorders began only in the seventies of the twentieth century. By 2011, as many as 75 different disorders had been identified and many treatment institutes had been established. The mysterious process of sleep has set a new paradox - sleep disorders were noticed only at a time when the way of life provided man with the best conditions for this renewal of energy.


Alien languages

Daniel Oberhaus's book Alien Languages ​​tries to answer the questions that Earthlings have been trying to solve for centuries.

One of them is: "Are we alone in the universe?", And it is always followed by the other, even more complicated: "If life outside the Earth exists, how would we communicate with it?"

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