When dreaming, the brain is resting or not. Methods for studying brain activity. How to charge the brain after sleep for work

A third of life is spent on sleep. Every person (including the blind from birth) sees dreams. Heterosexual men are more likely to dream not of women, but of other men. Such facts draw people's attention to the phenomenon of sleep. And although the activity of the human brain during sleep has already been studied enough to surprise, but not yet enough to answer all the questions of researchers.

The Phenomenon of Sleep in 10 Surprising Facts

Sleep stages and brain rhythms

According to some of the above facts, it can be seen that the whole dream consists of several stages, during which the brain demonstrates a different quality of mental activity. The transition from one stage and phase to another can be fixed by measuring the rhythms of the brain. (This was first done in the middle of the 20th century using EEG). The interaction of the phases depends on the daily rhythms, hormonal balance, body temperature and other factors.

In general, the entire process of sleep consists of a period with dreams ("fast") and a period without dreams ("slow"), which form a kind of changeable cycle. This cycle is repeated several times during the night. Moreover, if at the beginning of the night (and at the beginning general period sleep) the stage of non-REM sleep accounts for most of the time, then by the end of the night this ratio gradually changes towards the lengthening of the "rapid" stage. The “slow” stage consists of 4 phases:

After the "slow" stage, the "fast" stage begins, which is also called paradoxical.

The paradox here is that the extreme activity of the brain is combined with the complete immobility of the body. The body seems to be paralyzed. Only the eyes under the eyelids move quickly, which is clearly visible from the side. At this stage, a person sees dreams.

It takes about an hour and a half to go through all the phases and stages at the beginning of the night. Of these, 80 minutes are "slow" sleep and 10 minutes - "fast". Then the cycles are repeated. Moreover, the periods of the "slow" stages are reduced, and the "fast" ones are lengthened. So in the morning, in the last cycle before waking up, the ratio may already be 30:60 in favor of "REM" sleep. Such a number of morning dreams makes it possible to remember them after waking up - the likelihood that the alarm clock will ring in the paradoxical stage is higher.

During the day biological rhythms"Wake-sleep" are regulated by:

• homeostatic process that regulates sleep-wake patterns,
• circadian rhythm responsible for keeping track of the time of day.

The circadian rhythms of each individual person are stable, but different people they differ markedly. Because for real circadian rhythm strong impact exert external masking factors (stress factors, stimulants and energetics, illumination, environmental temperature), it is necessary to rely in the assessment, first of all, on indicators of body temperature and melatonin synthesis in low dim light.

The most famous differentiation on this basis is the division into "owls" and "larks". Part of the tendency to one type or another is due to heredity. The suprachismal nucleus of the hypothalamus is responsible for maintaining the rhythm, and subcortical structures are involved in the regulation.

The stability of this system, which regulates the circadian rhythm, depends on:

• short term memory,
• perception speed,
• cognitive ability,
• concentration.

The system controls those areas of the brain that are localized in the parietal and frontal lobes, behind the eye sockets. Depending on the time of day, in response to the same tasks, different reaction. The circadian system influences wakefulness rather than sleep. In particular, its action explains the improvement in cognitive functions that occurs at the beginning of the evening following the previous sleepless night.

At pathological course homeostatic and circadian mechanisms cease to complement each other and begin to conflict with each other, which leads to sleep disturbances, to its lack or total absence- sleep deprivation

Sleep disorders: what is it fraught with

Individual responses to sleep deprivation can vary markedly from person to person. However, in the same person, these manifestations are more or less similar.

Physiology in violations

In the absence of sleep, the regulation of the circadian rhythm is disrupted. This is due to the fact that melatonin, which is one of the main regulators of the daily cycle, is synthesized mainly at night, and in a person who “misses” the night, this synthesis does not occur in full. In addition, during sleep deprivation, the activity of the prefrontal and parietal regions of the brain and the thalamus is suppressed.

The prefrontal cortex plays leading role in the regulation of sleepiness. After 35 hours of continuous wakefulness, the activity of the temporal cortex begins to decrease. The reaction of this cortex to verbal learning in sleepy people differs from the norm. Lack of sleep also changes the composition of neuronal receptors on the cell surface: the number of dopamine receptors decreases, and the number of serotonin receptors increases. And although lack of sleep has little to no effect on memory capacity, it seriously slows down the reaction rate.

Genetic factors

• One of the most common disorders is the ability to fall asleep only in the morning. This condition is characterized by an extended circadian rhythm, when the individual "inner day" stretches up to 25 or more hours. The disorder is characterized by a polymorphism affecting the number of repeats in the PER3 gene - an association with the 3111C CLOCK allele.
• Reverse violation, when a person falls asleep much earlier conditional norm and its “inner day” is compressed up to 23 hours. The disorder is caused by a mutation in the PER2 gene.
• Mutations of the allele of the protein gene (HLA) DQB1 * 0602 - the main histocompatibility complex, found in 15-35% of sleep disorders are also associated with sleep disorders. healthy people who tolerate partial sleep deprivation worse than others.

Sleep disorders

The importance of sleep in maintaining life has already been illustrated by the consequences of "fatal familial insomnia". But there are other pathologies.

• Behavioral deviations. This disorder is characterized by involuntary movements of the arms and / or legs, which often occur during the transition between phases or in the stage REM sleep, resulting in a feeling that a person is physically participating in his dream. Often this deviation is observed in people with Parkinson's disease, which dictates the appropriate method of treatment.

• . With this disease, which affects 1 person per 2.5 thousand of the population, the mechanisms that regulate the transition to the "fast" stage are violated. A person can suddenly fall asleep "on the go" especially during monotonous work.

Another characteristic manifestation narcolepsy - cataplexy - involuntary and unexpected relaxation of the muscles of the body that occurs at the time of vivid emotional experiences (rage, joy, sexual pleasure, meaningful memories, etc.). Often, before falling with muscle relaxation, a person manages to consciously choose a place to fall.

To accompanying symptoms narcolepsy include:

• "paralysis" after awakening, in which a person remains for a few more seconds after he wakes up,
• vivid dreams, sometimes turning into hallucinations, at the moments of falling asleep and waking up,
• pronounced need for daytime sleep.

Depression and sleep disorders

Sleep disturbances can be both a symptom of depression and its cause. With depression, a person falls asleep longer, often wakes up during the night, sleep becomes superficial. 1 and 2 phases are lengthened and 3 and 4 are shortened. severe cases these last two phases of the deep sleep may be absent altogether. Because of this, depressed people do not get enough sleep at all, regardless of how long they sleep. The transition between phases in a state of depression occurs more abruptly.

Even more common violations of the paradoxical stage. A person with depression very abruptly enters a state of wakefulness. The “fast” stage, starting from the first cycle, comes much earlier. Unlike normal flow, depressive type cycle manifests itself in the form of a lengthening of the paradoxical stage not in the second, but in the first half of the night.

After overcoming depression, sleep usually returns to normal, but this does not always happen immediately. Sometimes pathological manifestations occur within six months. In cases where depression leads to sleep disturbances (and this happens in 9 out of 10 cases), drugs are used that stabilize emotional condition. Often, in order not to aggravate the situation under stressful circumstances, in conditions of impending depression or for a smooth exit from it, “soft” acting natural-plant complexes are used, which:

• normalize sleep,
• get rid of depressive states, fears and anxieties,
• improve the emotional background.

We are talking about such drugs as "HeadBooster", "BrainRush" and the like. Simultaneously with emotional stabilization, these complexes enhance mental activity help improve memory and attention. brain activity improves simultaneously with the improvement of the state of brain tissues and signal conduction in neural networks. The operation of these funds is based on the quantitative principle of gradual accumulation active substance during the entire recommended course, which determines the safety of drugs. Depending on the individual features body, the first results become noticeable after one to two weeks of use. Each element is selected so that it enhances the action of other components of the product.

The human brain during sleep does not stop its function for a second. While the whole body is resting, its activity continues. While a person is sleeping, energy is restored, memory is cleared of unnecessary information and the body is cleared of toxins. To understand whether the brain rests during sleep, what processes happen to it, an electroencephalogram was created that reveals accurate information about the work of the body. hot topic today is which part of the brain is responsible for sleep. The information presented is incomplete, although it is able to explain certain important points that occur at night in a dream.

The work of the brain in cycles

Previously, it was believed that when a person sleeps, brain activity gradually decreases, and then completely stops its work. With the emergence of the EEG, this theory was challenged. As it turned out, the brain does not sleep at all during sleep, but does a lot of work to prepare the body for the coming day.

During the rest period, the work of the body manifests itself in different ways, it all depends on the cycle in which sleep takes place.

Slow phase of dreams

When a person falls asleep, the vibrations of neurons in the gray matter slowly fade, there is a maximum relaxation of all muscles, the heart beat becomes slow, pressure and temperature decrease.

The part of the brain responsible for deepening into dreams is the hypothalamus. It contains nerve cells that inhibit the production of neurotransmitters, which are chemical conductors that are responsible for castling shocks between neurons.

The work of the body in the fast phase

During the period of fast-wave dreaming, the excitation of the thalamus occurs due to cholinergic receptors, the message in which occurs with the help of acetylcholine. These cells are located in the middle nucleus of the organ and the upper part of the pons. Their rapid activity leads to the appearance of a burst of swaying neurons. The gray matter in sleep during this cycle performs almost the same activity as during wakefulness.

Monoamine transmitters directed from upper lobe trunk to the cerebral cortex, do not feel such vigor. As a result, the supply of material from the thalamus to the cortex is carried out, although the person perceives it as dreams.

What part of the brain is responsible for dreams

Such a phenomenon as night rest has been of interest to many scientists for a long time. Previously, such famous philosophers as Hippocrates and Aristotle also made attempts in the knowledge of dreams. In the 20th century, Russian scientists Bekhterev and Pavlov conducted research on this topic. Scientists were also interested in the area of ​​gray matter, which was responsible for dreams.

Today in the central department nervous system of a person, the zone responsible for wakefulness and rest is determined. This area is called the reticular formation of the leading nucleus. brain stem, which is a web of many nerve cells engulfed by fibers extending from the sensory bases of the organ.

In this place there are 3 types of nerve cells that cause different biological active elements. One of them is serotonin. According to scientists, it brings about changes in the body that cause dreams.

Numerous studies have shown that when serotonin production stops, insomnia occurs. chronic form. So, the fact was revealed that the reticular formation, which is the zone of the center, is able to answer both for night rest and waking up. Moreover, the mechanism that causes lifting may prevail over the structure responsible for inducing sleep.

Research by Balkin and Brown

Dreams seem to refer to interesting phenomenon what happens to a person during a night's rest. The goal of the research conducted by Balkin and Brown is to identify the area in the brain where the greatest functionality occurs during the dreaming period.

To determine what is happening with the brain and the intensity of its blood flow, scientists used positron emission tomography. During wakefulness, the prefrontal cortex of the organ works, and when a person sleeps, the limbic system is active, which controls feelings, emotions, memory.

Brown and Balkin's work also shows that the main visual cortex is not active during sleep. In this case, the extrastrial cortex acts central department, which is the visual area of ​​the organ, capable of processing information about complex objects (faces).

Research from Wiskin University

Scientists in the study identified the area of ​​gray matter responsible for dreams. 46 volunteers participated in the experiment. During the rest period, the subjects noted the electrical waves of the brain laboratory way. Electroencephalography was used to isolate areas of nerve cells associated with visions, regardless of the cycle.

People were awakened from time to time and asked what they saw when they slept. The information provided was compared with the electrical work of the organ.

Subsequently, according to EEG data, it was revealed that during sleep there is a decrease in low-frequency work in a separate rear part of the organ cortex, which is associated with the appearance of visions. And when there was an increase in activity, nothing was dreamed of.

When the subjects told that they were dreaming, neural zones were activated all the time and vice versa were inactivated when they reported that they were not sleeping. And free from the usual predominances of rest, were present in the rear hot zone, which consists of:

• from the occipital cortex;
• precuneus;
• posterior cingulate gyrus.

By observing how this site works, the scientists predicted that the participant in the experiment would talk about visions when he woke up. Based on this, scientists concluded that these areas of the body are responsible for regulating human sleep.

How to turn off your brain before bed

Many are familiar with such a problem that as soon as you should go to bed, thoughts begin to burst into your head. If you do not calm the brain, and endure every evening similar condition, then daily well-being will be disturbed.

There are methods to turn off the brain before bed.

1. Understand the need for rest at night. Insufficient sleep can cause many diseases, anxiety.
2. Follow a regular schedule. Fall asleep and get up at the same time.
3. Turning off your head before going to bed will help a daily ritual, for example, by reading a book, but not in bed.
4. Make notes of unresolved issues and worries throughout the day.
5. Use the bed only for dreaming.
6. Create an acceptable environment. Silence, lack of light will help to relax the body.
7. Do mental exercises that will help turn off the mind.

If insomnia has not ceased to bother, you need to consult a doctor.

How to charge the brain after sleep for work

Most never thought about why separate group people are hyperactive in the morning, while others spend a lot of time to get into a natural working track. The difference is that the former start stimulating the gray matter early.

How to wake up the brain in the morning and feel cheerful, there are many tricks.

• take a cool shower;
• start the morning with an energetic tune;
• reading over morning coffee will help make the mind work;
• meditate;
• drink vitamins;
• do physical exercises;
• have a hearty breakfast;
• set an alarm to wake up the brain.

The human brain is a unique structure. Previously, it was assumed that during the period of dreams it is turned off completely. In the course of the research, it was revealed that this hypothesis has no basis, and, therefore, is excluded from the facts. When a person sleeps, there is an activation of neural connections responsible for the functionality of the body as a whole.

The brain uses periods of sleep in order to get rid of the toxins accumulated in it during the day.

A group of American scientists believe that this mechanism is one of the main causes of sleep. They found that during sleep, neurons decrease in size and spaces between them are filled with brain fluid.

Scientists also suggest that disturbances in the mechanism of removal of toxic proteins may be related to the occurrence of brain diseases.

Biologists have long wondered why all animals go to sleep, despite the fact that it makes them more vulnerable to predators.

Sleep is known to play important role in the formation of memories and the processing of learned information, however, scientists from medical center at the University of Rochester concluded that one of the main functions of sleep may be brain cleansing.

The brain has limited number energy, and it looks like he has to choose between two different functional states- wakefulness or sleep - says Dr. Maiken Nedergaard, one of the researchers.

The scientists' findings are based on last year's discovery of a so-called glymphatic system that operates in the brain specifically to remove harmful substances.

Scientists who scanned the brains of mice found that during sleep, the glymphatic system increases its activity by 10 times.

Brain cells - perhaps the glial cells that surround and support neurons - shrink during sleep. This leads to an increase in the intercellular space in the substance of the brain, which in turn increases the flow of fluid, which removes toxins from the brain.

According to Dr. Nedeligaard, this mechanism is critical for normal functioning brain, but it can only work during periods of sleep.

While this is just a guess, it looks like the brain is wasting a lot of energy pumping fluid through its tissues, which is inconsistent with information processing, she says.

The true significance of these results will only become apparent after human studies, she says, and conducting such experiments using magnetic resonance imaging is relatively easy to set up.

Many degenerative diseases of the brain, leading to the loss of its cells - such as Alzheimer's and Parkinson's diseases - are accompanied by the formation of plaques in the brain vessels, consisting of toxic proteins.

The researchers believe that the brain clearing mechanism is involved in the occurrence of such diseases, but stress that more research is needed.

How the brain works during sleep

Each person spends about a third of his life in a dream. Everything that I have been doing all day, what events have happened, what people I have communicated with, what tasks - easy or insoluble we have set ourselves, what we still have to do in the near future - all this and much more is digested and puts in its place by our brain during sleep. Even the information that you forgot during the day. It turns out that at this time our brain does not rest, but is very active. How does the brain work during sleep?

I remember from my school days how in literature lessons they were asked to memorize large excerpts of prose from literary works. This is not a poem for you, well, you can’t remember it in any way. Until my mother advised me to read the text directly from the book at night and put the book under the pillow. And so for several nights in a row until the very lesson of literature. At the lesson, the very first teacher calls me to tell a passage, and I have a fear that I don’t remember anything. And suddenly it is not clear where from some memory cell the lines of a given work appear by themselves, and I tell the whole passage without hesitation. The same thing happened at the institute during exams, when you prepare for a long time and hard, you go to bed tired with the feeling that you don’t remember anything, and at the exam the correct answer pops up in your head from somewhere.

Scientists have found that during sleep, a system appears in the brain that protects the information received. Moreover, especially the information that was presented with emotional experiences.

In addition to the fact that the brain does not miss anything that we have received and seen during the day, it independently builds into logical chains everything that seemed unsolvable during the day, so in the morning we seem to ourselves wiser than we were yesterday. This is where one of the first Russian proverbs “Morning is wiser than evening”, used in many folk works, comes from. This simple folk wisdom, it turns out, has a pretty serious scientific confirmation. During sleep, new information does not enter the brain, and the information already received is processed by the brain using the chronological ordering of your events and analysis using your already accumulated life experience. You probably know from a school course in chemistry that Dmitri Ivanovich Mendeleev's Periodic Table chemical elements dreamed in a dream.

It turns out that a person is sleeping, resting, and his brain is continuously working at this time, a person not only restores strength, but also sees dreams. Scientists prove that all warm-blooded animals, even some birds, also dream in their sleep. In their opinion, this is the process of rebooting the human brain, during which all unnecessary information is “thrown away”, and important in the morning will be given to you by your brain as the only correct one, filtered and ordered by it during sleep.

If you didn’t have a colorful and rainbow dream, but some kind of horror story, this is also one of the results of the brain’s work in a dream - a reaction to your stresses and fears. Such a dream calls to pay attention to some important point life.

But let the work of your brain during sleep be aimed at processing only positive, joyful information, and let you dream only rainbow dreams.

During sleep, the brain works with more activity.

Scientists at the University of California have proven that the brain during sleep, works with greater activity, as if remembering something, for example, the information that experienced teachers gave him when he took courses in tax consultants.

American scientists have also carried out several scientific research, in the area of ​​the human brain during sleep. Based on this, scientists have come to the general opinion that during sleep caused by anesthesia, the human brain is actively working. His activity is directly related to the memories of any events.

For a more detailed study of the brain, American scientists investigated the behavior of some brain neurons, which by their nature are involved in the process of memory formation.

Thanks to modern technology, experts were able to study the activity of individually selected brain neurons, and they also determined at what exact moment the most active work of the brain begins.

This study was led by Professor of Neurophysics Mayank R. Meta. were carried out on laboratory mice. Throughout the study, scientists were able to study the mechanisms that take place in the new and old centers of the brain, the hippocampus and neocortex.

A little earlier, previous studies showed that the connection between new and old centers of the brain is considered critical for the formation of memory during sleep. Today, new research results show the opposite. The function of memory formation during sleep characterizes the same effect on both parts of the brain.

Scientists have discovered in the cerebral cortex neurons that are activated during the so-called slow sleep. This discovery may help in the search for remedies for insomnia and some neurological disorders, according to the authors of the study.

Dmitry Gerashchenko of Harvard Medical School and his colleagues in experiments with animals discovered a group of cells in the cerebral cortex that are active during spontaneous or forced sleep associated with a prolonged inability to fall asleep. They identified a specific type of cortical neuron that produces nitric oxide, a substance that regulates blood flow in the brain. As the authors of the article established, these neurons are active during non-REM sleep in the cerebral cortex of mice, rats and hamsters.

Non-REM sleep is one of the phases of sleep, which accounts for about three-quarters of its duration, this is the phase of the deepest sleep. Hypotheses have previously been put forward that this stage is associated with the restorative functions of sleep, as well as with the ability to learn. Groups of neurons that are active during sleep have previously been found in the hypothalamus and forebrain. Until now, however, the role of cortical cells during non-REM sleep has remained unclear, as it was assumed that they are at rest during this stage.

Now it's written great amount publications concerning the work of the brain during sleep. It's all terribly complicated, all those sleep phases, brainwaves. AT recent times I am more and more worried about the growing gap between the real world and the world of dreams. Similar thoughts wandered in me and looked for a reason to go to the pages of my blog. It was inspired by a post I read the other day.

The fact that in early childhood for us there is practically no difference between sleep and wakefulness, I think everyone knows. Why does this phenomenon take place? It's all about thinking, or rather in its place. As children, we think almost entirely in the right hemisphere. Knowledge of the world occurs through images. Therefore, childhood memories are so similar in structure to dreams.

As I wrote earlier, gradually growing up, we are taught to think in ready-made concepts, definitions that are stuffed into our brain. This is the whole trouble and danger of left-brain thinking. As a consequence, we observe the asymmetry of our brain. Our left hemisphere is overloaded during daytime work. In order to somehow even out the situation, while our left hemisphere is sleeping, the right hemisphere enters the scene and we plunge into the world of imaginative thinking.

All those images that we observe during the day are completely intercepted by the right hemisphere. Not a single detail escapes him. Thinking in images differs from thinking in concepts in that the world accepted as he is. With this way of perception, it is impossible to miss a single detail.

Such work of the brain during sleep reveals to us endless possibilities. The whole trouble is that we have practically lost the ability to understand figurative thinking; we are again trying to interpret it within the framework of concepts known to us immediately after waking up. This is the mistake of all dream books and interpreters of dreams. Right hemisphere works for us, only it is difficult for us to understand his speech.

In the light of all these considerations, it remains unclear how, on the basis of daytime images in a dream, we are able to see the future. Probably, during the day we are constantly surrounded by so-called guiding signs, by which it is easy to predict the outcome of all events.

The fact that we see all this in a dream once again confirms our inattention and fixation on the petty problems of the day. It turns out that those who claim that the present past and the future exist simultaneously are right? Or maybe it's the Earth's magnetic field that affects our mind?

Sources: www.rosbalt.ru, www.realfacts.ru, www.trental.ru, www.sunhome.ru, hronist.ru

Article content

Need daily sleep conditioned not only by human desire and physiology, but also by science. Absolutely every person spends about a third of his life on this occupation. Everything that he did the whole previous day, what tasks he solved, what he thought about, what he planned, what memories he came across, the brain digests and puts them “on the shelves” when a person is fast asleep. It turns out that when a person is unconscious and plunges into the arms of Morpheus, the brain continues its active work. Consider how the brain functions during sleep, what it actually does and how it behaves.

What does the brain do at night

When we sleep, our brain continues to function. This activity, activity of the brain is due to the peculiarities of its structure. The list of his tasks at this moment is as follows:

1. Acceptance is vital important decisions. Studies have shown that the brain is able to take operational decisions for any questions or concerns. The source Current Biology published the results of studies in which respondents were asked to sort words into categories by pressing a button, while still being able to fall asleep. The experiment continued into sleep, as the brains of the participants demonstrated the ability to make decisions even after the body fell asleep.
2. Memory classification. Studying the question of what happens to our brain during sleep, it can be noted that it is engaged in the processing of memories and the loss of connections with old moments. He sorts human memory so that the right moments are not forgotten. According to Dr. M. Walker, who works at the University of California, if a person after healthy sleep attend a piano lesson and sleep the next night right amount time, the material will be learned and reproduced 20-30% better than when testing knowledge immediately after the lesson is over.

3. Gets rid of waste and toxins. As soon as the body falls asleep, the brain continues to work actively, ridding it of harmful substances. This fact is confirmed and supported by a series of research activities. But increased amount these elements can lead to many pathological conditions, so the benefit of the brain in this direction is undeniable.

4. Training in physical labor. During REM sleep, information about motor options is transferred from the cerebral cortex to temporal region. This phenomenon allows you to carefully think through and flawlessly perform tasks related to physical labor. Now it is clear which part of the brain is responsible for the execution exercise and daily activities.

As can be seen from the above, the functioning of the brain during sleep continues, and even when we sleep, it performs a large number of tasks.

The work of the brain in cycles

The whole process of human sleep at night consists of several cycles of "slow - fast process". According to the public theory, we sleep to ensure the processing of information received during the day or the previous day. Classical sleep includes 4 stages of non-REM and 2 stages of REM sleep. Information is transmitted in a reorganized form only after the completion of the third cycle. But the brain does not turn off in the next 1-2 cycles, but continues to work.

In the process of immersion in the world of Morpheus, brain structures temporarily lose their functional interconnections that promote wakefulness. This phenomenon can be tracked on electroencephalograms. Each of these structures closes in on itself, and then tunes in the right way and is subject to regulation, which cannot be done during wakefulness, when the "gray matter" is in active interaction With environment. A sleeping person's head works a little differently.

Even when we sleep, our brain is still working.

At the stage of slow sleep, the regulation of internal rhythms occurs with respect to each structure of the brain, while at the stage of the fast process, harmonic relationships are established between these elements. In general, sleep has one main task - to adjust the biorhythms of the body to optimal mode which is individual for each person. This standard is created in the process of wakefulness, and this or that behavioral program, laid down at the genetic level, acts as a base. If the model is formed and works smoothly, it is enough to rest a small amount of sleep. If there are failures, the person sleeps longer.

Interestingly, the need for sleep has an inverse relationship with the amount of information received: the more it enters the gray matter, the less sleep necessary. This may be due to the fact that in the process of obtaining enhanced mental load a person sleeps less than in the case when he most spends his time watching TV.

Rest of the brain during sleep

Does our brain rest during sleep? The issue is the subject of controversy among many people. And this is not unreasonable. In fact, as soon as a person goes into the world of dreams, the brain is rebuilt to a different mode of operation. If during wakefulness he did not have the opportunity to analyze events and classify thoughts, then when a person fell asleep, she appeared. Therefore, in the first cycles, the brain is engaged in these tasks, and at the end of this work (usually closer to the morning) it has a little time to rest. But this does not mean that it completely “turns off” along with the body, we can say that it simply turns on the “economy” mode. Therefore, from the side of the brain, sleep is perceived differently than from the side of the body.

Brain function and dreams

When the brain structures function, they establish mutual connections with each other, as if talking. This fact is fully proven various dreams. Also in this process there is an active training nerve centers: Cells that were inactive when awake begin to perform a kind of functional gymnastics to maintain optimal shape. It is for this reason that after stress a person sleeps “like a log”, because his cells have already received a shake-up and do not need additional information in the form of dreams.

Slow phase of dreams

In total, the slow stage accounts for about 75-85% of all sleep, and it includes several states:

• nap;
• sleep spindles;
• delta sleep;
• deep dream.

As a person sinks into sleep, many bodily functions change. In the first stage, called drowsiness, and also in the second stage, the pulse becomes more rare, blood pressure is subject to decrease, blood flows more slowly. As soon as the sleeper plunges into the state of delta sleep, his pulse noticeably quickens, and the pressure rises. Non-REM sleep is the phase responsible for regulating internal rhythms for each brain structure and every organ.

The work of the body in the fast phase

The way the brain works during REM sleep is somewhat different. Basically, the process of REM sleep can be divided into 2 main stages:

• emotional;
• unemotional.

They alternately come to replace each other and act like this several times, and the first stage is always longer.

How does REM sleep differ from slow sleep?

There are several points that distinguish one phase of sleep from another, and you should take them into account.

1. There are 4 stages in non-REM sleep and 2 in REM sleep.
2. During slow-wave sleep, eye movements are smooth at first, and at the end of the stage they stop altogether. In the fast phase, the opposite is true - the eyes move continuously.
3. The state of the autonomic nervous system also differs: in the first case, a person grows faster, since there is a more active production of growth hormone.
4. Dreams are also different. If a we are talking about the fast phase, the pictures are saturated various actions, are brightly colored. In slow-wave sleep, the plot is more calm or may be absent.
5. Awakening process. If you wake an individual during REM sleep, he wakes up much easier, and subsequently will have much better health than a person awakened in slow sleep.
6. Brain temperature on the way to slow phase sleep gradually decreases, and in the fast phase due to a rush of blood and active metabolism, on the contrary, it increases. Sometimes it can exceed normal rate observed during wakefulness.

Another important question is which part of the brain is responsible for sleep. After all, until recently it was not known in which area of ​​the brain the work associated with dreams takes place. Scientists from the University of Wisconsin as a result of the study were able to make sensational discovery. It was proposed to take part in the experiment 46 people who had registration of electric waves. High-density EEG was used to isolate regions of neurons responsible for dreams regardless of sleep phase. The subjects were awakened several times and asked about their dreams. And then the received answers were compared with electrical activity.

The data obtained during the study showed that during sleepy state decreased activity in the posterior cortex was directly related to the occurrence of dreams. Conversely, when an increase in low-frequency activity was observed in the same area, the subjects said that there were no dreams, that is, nothing was dreaming at that time.

Brain cleansing

American scientists in the course of some studies found that sleep is also needed to cleanse the brain of toxic elements. According to their observations, during sleep, the brain consumes the same or even more energy than during wakefulness. During tests on rodents, experts found that during sleep, activity does not decrease, but only goes into a different direction. At night when the cleansing takes place internal organs from accumulated toxins with the help of lymph, the brain is also cleansed.

A doctor from the New York Medical Center said that the resource of the brain implies certain limitations. Gray matter is capable of doing one thing: either actively processing thoughts, or ensuring the removal of toxins. If this process were observed in daytime, not a single person would have the possibility of normal decision-making. And if there was a gradual accumulation of toxins in the brain, there would be huge probability occurrence of Alzheimer's disease.

What conclusion can be drawn

Thus, we have learned how human brain during sleep, how much energy it consumes, and in what mode it functions as soon as we fall asleep. Our "gray matter" is the object of observation and debate by many scientists. When we are in the arms of Morpheus, he begins his work, unknown to us, solving a large number of problems. During wakefulness, he is also active, but acts in other directions. The human brain is a complex structure that requires detailed study and research.

All mammals and warm-blooded creatures on the planet, and even birds, must sleep. This is a feature of the body that scientists cannot fully unravel and understand how it works. However, in the 50s of the last century, an electroencephalogram (EEG) was invented - this is a technique that allows you to monitor what happens to the brain during sleep and other organs and systems. At the same time, a person sleeps, his rest is not disturbed, which makes it possible to obtain reliable data on the functioning of the body.

However, the most relevant question is how the brain works during sleep. The answers to it have been found only partially, but they can explain some important processes occurring during the night's rest.

Sleep activity

Previously, it was believed that in a sleeping state, brain activity gradually decreases, and then its activity completely stops. However, the emergence of the EEG completely refuted this theory. It turns out that the brain never "dozes" in sleep, it does a titanic job to prepare us for the next day.

When we sleep, we go through two main phases: non-REM and REM sleep. Slow-wave sleep is also called orthodox or deep sleep, it is from it that the night's rest begins. This is followed by the fast phase, also called the paradoxical or rapid eye movement phase.

The brain behaves differently during sleep, depending on which phase it goes through. Let us consider in more detail what mechanism of action of neurons in it is launched at certain moments.

1. brain and slow sleep. During falling asleep, neural oscillations in the brain gradually fade, all the muscles of the body relax as much as possible, the heartbeat slows down, pressure and body temperature decrease. Sleep is controlled by a part of the brain called the hypothalamus. It has a group of nerve cells that inhibit the production of neurotransmitters (chemical transmitters responsible for the exchange of impulses between nerve cells). The activation of this group of brain neurons is responsible for the beginning of the night's rest.
2. brain activity during sleep fast phase. During paradoxical sleep, the excitation of the thalamus is carried out by cholinergic receptors, in which the transmission of excitation occurs through acetylcholine. These cells are located in the midbrain and the upper part of the pons. Their high activity leads to the fact that a surge of neural oscillations appears. The brain during this phase of sleep performs almost the same functions as during wakefulness. However, monoamine transmitters, which are sent to the cerebral cortex from the upper part of its trunk, do not experience such activity. Consequently, the transfer of information from the thalamus to the cortex occurs, but we perceive it as a dream.

Sleep Detox

The brain performs in sleep various functions, but latest research confirmed that the main one is detoxification. According to experts, the glymphatic system, discovered just a few years ago by scientists, is responsible for this process. As it turned out during experiments conducted on mice, the activity of this system during sleep increases by more than 10 times. The process of removing harmful protein compounds helps prevent pathologies such as Alzheimer's and Parkinson's. The cleanup takes place as follows:

• cells that support neurons in the brain shrink during sleep, they seem to shrink;
• intercellular space increases in the medulla;
• the brain fluid practically flushes out the toxins that have accumulated between the cells.

As scientists suggest, the brain spends a lot of energy on detoxification. It may be that he cannot be awake and "clear" at the same time, and therefore we are forced to spend some time sleeping.

Reliable data on this subject will be known only when experiments begin to be carried out on humans, and not on animals.

Other features

Despite the fact that detoxification is considered by scientists to be one of the most important discoveries recent years In addition to this task, the brain performs other important functions for the body during sleep.

Consider what kind of work he does, and how it affects our well-being during the day:

Summing up

The human brain is a unique structure, the possibilities of which have not yet been fully discovered. If earlier it was believed that it is completely turned off during sleep, now it is known that this is not the case. While we rest are activated neural connections, which are responsible for various functions of our body.

Adequate sleep is important for maintaining normal physical and psychological state a person, therefore he needs to allocate the allotted time.