What happens to the brain while we sleep. All the most interesting things in one magazine How to sleep with maximum benefit for yourself
What happens to our body while we sleep
If you think that your brain and body spend its hours of sleep in a blissful state of inactivity and calm, then you are wrong. A lot happens inside us while we sleep.
A person spends a third of his life sleeping. Those who do not comply with this requirement are ultimately punished with a whole bunch of illnesses, from endocrine, cardiac, gastric, to cancer and mental disorders.
Here are a few processes that occur in our body while we sleep:
Digestive juices: The amount of acid in our stomach usually decreases while we sleep, but if we have an ulcer, it instead increases.
Performance hormones: two female sex hormones (follicle stimulating hormone and luteinizing hormone) are released during sleep. In addition, growth hormone is released in children and adolescents when they sleep.
Kidneys: The rate at which our kidneys filter waste slows down while we sleep. This decrease in kidney activity explains why the first morning urine is so concentrated.
These changes from wakefulness differ little compared to what happens in our brain, muscles and circulatory system.
Our breathing, heartbeat, and muscle movements change depending on the NREM and REM stages of sleep. During certain stages of NREM sleep, many of our body functions operate at a slower rate compared to normal waking levels, including brain activity, heart rate, blood pressure, breathing and body temperature. Our muscles are in a relaxed state and, for the most part, blood flow to the brain remains unchanged.
Based on brain waves, scientists have learned that we go through five stages of sleep. Stages one through four are NREM (non-rapid eye movement). The last stage is REM (rapid eye movement sleep). Our brain cycles in five stages of 90 to 110 minute intervals four to six times per night.
In the REM stage, each of these processes increases above normal awakening levels. Additionally, blood flow to the brain can increase anywhere from 50 to 200 percent and increases sexual arousal. Our eyes move back and forth, up and down, as if we are awake and focus on a moving object. The muscles in our heart and lungs also continue to move, but the muscles in our limbs are paralyzed.
During REM, the parts of our brain responsible for learning become active. It may be no coincidence that REM is the stage of sleep when we dream, although scientists cannot understand why we dream at all.
While there are still many sleep-related questions that need to be answered, scientists have learned very little about what happens to our bodies when we don't get enough sleep. We all know that our ability to think quickly and clearly, to decide math problems, remembering details, and performing some physical tasks decreases when we are sleep deprived. ?
For adults, the typical amount of sleep needed is 7 to 8 hours per night.
Even scientists can only guess about many of the processes that happen to us in our sleep. Andrea Rock spoke about several studies of the last century, visited scientific laboratories and took part in experiments on her own brain. And then she wrote a book called “The Brain in a Dream.”
Here is a short summary of what Andrea Rock wrote about. If you understand that this book is just for you, run to the bookstore. There is still a lot of interesting things in it.
Why do we need dreams?
Based on the research of Calvin Hall, who began collecting information about dreams different groups people back in the 1940s, we are much more likely to encounter failures in our dreams than successes. Based on 50 thousand reports on the nighttime experiences of subjects, we can conclude that our dreams with the onset adolescence filled with aggression and negative emotions and remain that way for life.
Sometimes dreams repeat themselves because their content is consistent with a certain emotion. Let's take, for example, a common dream about how we come to an exam in a subject that we have not studied at all or have taught poorly. Variations: We are on stage, performing in a play for which we do not know the text, or we have to give a speech, but have no idea what to talk about. What is common in all these situations, of course, is the emotion that fuels the dream: anxiety about one’s own unpreparedness. Details depend on personal experience- an actor sees himself on stage, a politician or lecturer - at the pulpit.
During REM sleep phases(phase R.E.M., from English rapid eye movement - the phase during which the highest brain activity is observed; accompanied by rapid movements of the eyeballs), the brain processes both genetically stored information about survival and knowledge and experiences acquired during wakefulness. Neuroscientist Antti Revonsuo suggests that this property appeared in lower mammals and human ancestors, who trained the most important life skills (hunting, fighting, running) in their sleep.
How the brain works during sleep
The REM phase is dreaming in action: if during the most active movements eyes under the eyelids will wake up a person, he will clearly remember what he just dreamed. This was first discovered by the discoverer of the REM sleep phase, Eugene Aserinsky, thus proving that the brain continues to work during sleep.
Another researcher, William Dement, divided sleep into five stages:
- Falling asleep. This phase is characterized by hallucinatory images, most often associated with events experienced during the day. Light sleep. This period lasts from 10 minutes to half an hour. The first stage of slow-wave sleep. The second stage of slow-wave sleep. NREM sleep is the deepest phase of sleep, during which many people talk or get out of bed. REM phase.
During REM, our muscles are completely relaxed, we are practically immobilized, although at the same time eyeballs rotate under closed eyelids, and arms and legs may shake involuntarily. From falling asleep to the onset of the first stage of REM sleep usually takes from 50 to 70 minutes, and then REM repeats every 90 minutes. During the first half of the night, slow-wave sleep prevails, periods of REM sleep can be short - about ten minutes, then the picture changes - periods of slow-wave sleep are shortened, REM periods are lengthened and can last 20 minutes, and closer to the morning and up to an hour.
What do dreams mean and do they need to be interpreted?
At normal operation brain, we see dreams every night, but we remember only a small part of them. Even those who don't usually remember their dreams can easily talk about them if they wake up during REM sleep.
With age, the plots of dreams become more complex as a person gains experience, and images and emotions emerge in the mind that are blocked during wakefulness. Many of the experiences appear in dreams only after several days or even weeks - this pattern is called dream lag effect.
Sigmund Freud said that dreams are the “royal road” to the unconscious, in them we seem to hide hidden desires and feelings. But often dreams are a modified version of reality(this is confirmed by survivors of psychological trauma, eyewitnesses of terrorist attacks or veterans of military operations). But the brain’s search for metaphors and hidden connections only proves that it works to our advantage. Processing information and emotions in a dream helps to get rid of anxiety, because even if we don’t remember the dreams of the past night, they will be woven into consciousness and prompt the necessary way of thinking during the day.
As anti-Freudians like to say, sometimes a cigar is just a cigar. Freudian psychoanalyst Mark Solms agrees that "Freud may have been wrong" in arguing that the strange, bizarre features of dreams are the result of the mind's attempt to censor and camouflage taboo desires, and that they arise from the strange physiological state of the brain during sleep. when rational systems frontal lobes almost inactive.
How to sleep with maximum benefit for myself
Dreams play a significant role in the brain's assimilation of new information. Most favorable for learning late stage REM, although other phases of sleep are no less important. It's best to arrange "quiet hour" between activities that require active mental activity.
While we sleep, our body continues to work actively. Some processes in it are activated, others, on the contrary, are stopped. We are unable to monitor our body during sleep. But whatever happens to us.
The nose is "sleeping"
“You can’t wake me up with guns,” the lovers of sweet sleep confidently declare. In fact, sharp sounds, regardless of the nature of their occurrence, bring a person out of any stage of sleep, even the deepest, and this is the principle of the alarm clock. However, it is interesting that even the most active odors perceived during sleep are not able to awaken the sleeper, although the brain identifies them.
Most likely, the information received by the olfactory organs will smoothly merge with the image projected by the brain, and while your partner is desperately running around with a cup of coffee, you will simply continue drinking coffee on top of the Eiffel Tower in your dream.
Neither the pungent smell of pyridine nor the pleasant smell of mint, which Brown University (USA) scientists used in their experiment, awakened the participants in the experiment. This explains the large percentage of deaths of those sleeping during a fire - people simply do not notice the intense smell of burning.
Movements in sleep
It would seem that the lying position and the absence of the need for physical and mental activity must be expressed in a state of absolute rest. In fact, the body continues to react to external stimuli, such as light, noise, and room temperature.
Due to gravity, areas of the body in contact with the surface are subject to maximum pressure, which makes it necessary to change position several times during sleep. Average, healthy man makes about 25 different movements during several hours of sleep.
Moreover, 70% of them have a detrimental effect on the intensity of sleep, preventing us from achieving its deep phase, which is necessary for good rest and energy restoration. During the deep sleep stage, most muscles relax but are not paralyzed, keeping the sleeper from becoming overly active. These processes explain the danger of sleep in a state alcohol intoxication when a person does not change posture for several hours, which is fraught with high blood pressure on separate areas body and the prospect of neuropathy.
Sleeping eyes
IN initial stage When sleeping, the eyes roll upward, preventing light from reaching the retina even with half-open eyelids. By the way, by the eyes you can determine what phase of sleep the person is in.
In the deep sleep phase, the eyeballs move slowly under the eyelid due to active blood flow to the muscles and internal organs. The deepest sleep phase is also characterized by slow eye movements, but it also reduces heartbeat and the general rhythm of life. And during REM sleep, blood supplies the sleeper’s brain, and the thought processes, we see colorful dream pictures, and the eyes move in accordance with them. These processes are universal for both humans and animals - watch a sleeping cat and understand what trajectory the sparrow flew in her dream today.
The morning is wiser than the evening
The brain, of course, does not turn off during sleep, but only switches to a different mode of operation, continuing to control the ongoing processes in the body. Brain cells reduce the speed of their response to peripheral stimuli and begin to work on organizing and classifying information received during wakefulness.
This data is sorted, compared with existing data and sent for storage to the appropriate areas of the brain. Constant lack of sleep takes away time for processing information, as a result of which the data is confused, and the person begins to complain about the state of memory.
In 2004, German scientists from the University of Luxembourg taught a group of volunteers to solve mathematical problems of a certain level. Participants were offered about 100 tasks. After the first part practical classes half of the students were asked to sleep for twelve hours, while the others stayed awake.
During the second part of the seminar, 23% of those who were awake suggested best option problem solving, while in the group of those who managed to sleep, this figure was 59%. This proves that during sleep, information is collated and organized, allowing one to find the optimal solution to an existing problem, which the waking person is not even aware of.
Brain cleansing
There are two modes brain activity– the waking mode, when a person actively thinks, thinks logically and makes decisions, as well as the sleep mode or “washing” the spaces of the nervous tissue with cerebrospinal fluid when we rest.
Toxins are concentrated not only in the kidneys and liver, but also in the brain fluid of the body. It is during sleep that the glial cells that surround and support the neurons of the brain shrink, thereby increasing the intercellular space and increasing the flow of fluid that removes toxins from the brain.
During sleep, the glymphatic system increases its activity approximately 10 times. If this does not happen, then plaques form from existing toxic proteins in the brain, leading to the development of Alzheimer's and Parkinson's diseases. Unfortunately, pumping fluid through brain tissue requires a lot of energy and is incompatible with information processing processes, so living organisms cannot do without full, long sleep.
Height and weight
“If you fly, it means you grow!” - my mother said in childhood. We hasten to please you - it is not at all necessary to experience the state of flight in a dream, and if you measure your height before going to bed and immediately after waking up, then in the second case you will find “added” 05.-1 centimeter.
During sleep, the load on the intervertebral discs, they are moisturized, stretched and take up more space without being subjected to body pressure. Thus, the spine straightens, although in the evening, especially after prolonged vertical wakefulness, growth returns to its original parameters.
Sleep also produces the hormone leptin, which reduces hunger, while lack of sleep will produce the opposite hormone, ghrelin, which increases appetite. True, for the first one to work actively, you need to sleep at least seven hours, and lack of sleep (4-5 hours a day) actively prevents the reset excess weight, even with a strict diet and physical training.
If you overeat before bed, it is best to sleep on your right side, this will allow your stomach and intestines to cope with the load. Of course, you should eat food no later than 3-4 hours before bedtime, and then you are guaranteed a healing effect.
Anti-aging effect
Sophia Loren claimed that the secret of her beauty is good sleep. We have no doubt about the veracity of this statement. During sleep, body temperature and blood pressure drop, the heart muscle relaxes and restores, and the body switches to energy conservation and accumulation mode.
In addition to these processes, the production of collagen, a protein that strengthens blood vessels and gives the skin elasticity, increases. Due to these properties, collagen is often used in cosmetic procedures and creams, but nothing can replace its natural production by the body.
For this reason, creams containing retinoids that promote collagen production are recommended to be used before bed. In addition, during sleep, body tissues are renewed, but the production of growth hormone, somatotropin, can be hindered increased level insulin. Therefore, if you plan to get all the benefits from sleep, you should not get used to late dinner.
During sleep, the cleansing of skin cells accelerates (especially in the first half of the night), improves oxygen exchange, toxins are removed and tissue strength increases, which leads to a reduction in wrinkles, increased elasticity and a visible rejuvenating effect.
Body temperature drops
Because most of the body's muscles become inactive during sleep, the body burns fewer calories than when awake, so body temperature drops. Scientists have found that the most low temperature body in a person during sleep - at 02:30.
The eyes are moving
Although closed by eyelids, the eyes move in sleep. Their movements even differ depending on the stage of sleep. At first they roll smoothly, and then, when a person falls into deep dream, they begin to move quickly. However, a person, as a rule, does not remember this.
The body twitches convulsively
Sudden twitches and jerks are most often associated with the first stages of sleep. They are generally harmless, but can be quite strong - sometimes to the point of actually waking you up.
Muscles are paralyzed
There is a compelling reason why most muscles become paralyzed during sleep: if they were active, a person could act while asleep, and this, of course, would be extremely dangerous.
Skin repairs itself
The top layer of skin is made up of compacted dead cells that are shed throughout the day. During sleep, the skin's metabolic rate increases and many cells in the body exhibit increased production and decreased breakdown of proteins. Because proteins are essential for cell growth and repair of skin damage from factors such as UV rays, deep sleep can truly be called "beauty sleep."
The brain forgets unnecessary information
“We take in a lot of information throughout the day, and fortunately most of it is forgotten,” says sleep specialist Christopher Colwell of the UCLA School of Medicine. “If you remember everything you learned or heard all day, then the brain, in order not to become overloaded with information, will begin the sorting process during sleep, weeding out what is unnecessary.”
Throat narrows
Unlike most other muscles, the throat muscles are not paralyzed during sleep because they are needed for breathing. However, they become more relaxed, causing the throat to narrow. It also likely contributes to snoring.
The body produces hormones
During the slow-wave sleep phase human body produces growth hormones that stimulate cell growth, reproduction and regeneration. Sleep, even if it is during the day, promotes the release of prolactin, an important regulator of the immune system.
The immune system is at its peak
Lack of sleep has been shown to affect the immune system. One study found that people who were given a flu shot and deprived of sleep the next night were unable to produce the antibodies needed to protect against the flu. Therefore, as soon as a person experiences the first signs of infection, one should get as much sleep as needed. immune system to overcome the disease.
Man losing weight
During sleep, a person loses fluid by sweating and exhaling moist air. This happens throughout the day, but drinking and eating will negate any weight loss. Therefore, quality and long sleep is necessary for any diet to achieve success.
My mouth becomes dry
Since saliva is mainly needed for the feeding process, and a person does not eat during sleep, the salivary flow at night is reduced. Consequently, a person may feel dry mouth and thirsty when waking up in the morning.
A man can grind his teeth
It is estimated that around 5% of people suffer from a strange condition known as bruxism. This parafunctional activity manifests itself in excessive grinding of the teeth and can ultimately lead to tooth damage. Scientists aren't sure what exactly causes this condition, but they think it may be a form of stress relief.
The body lengthens
It has been found that people can be several centimeters taller in the morning than they were the night before. While sleeping in horizontal position the spine is stretched because the weight of the body does not press on it from above.
Arterial pressure is decreasing
During sleep, a person experiences what is called a "night dip" in blood pressure.
A person can walk in his sleep
WITH scientific point vision known as parasomnia, sleepwalking and other sleep activities include behaviors, emotions, sensations and dreams that typically occur during transitions between certain stages of sleep. Parasomnia is mostly harmless, but there have been cases where people have been injured while sleepwalking.
A person can become sexually aroused
Both men and women can become sexually aroused in their sleep. Because the brain is more active during sleep, it requires more oxygen. As a result, blood flow throughout the body increases, causing the genitals to swell.
We dream
The content and purpose of dreams are not fully understood, but it is known that the average person sees 3-5 dreams per night. We mostly see dreams in the first phase of sleep, when our brain is more active. However, we forget most dreams immediately and quickly.
The brain makes decisions
Recent research has shown that the brain can process information and prepare for activities during sleep, effectively making decisions during sleep. unconscious. In fact, our brain can even make important conclusions and discoveries while we sleep.
Oh this flatulence
It is unlikely that anyone will be happy to know about this, but at night the muscles anal sphincter relax slightly, releasing gases accumulated in the intestines. Good news is that during sleep a person’s sense of smell is not as acute as during wakefulness, so the release of gases at night, as a rule, goes unnoticed.
The body is completely cleansed of toxins
Removing toxins allows our body and brain to recover. In poor sleepers, filtration is not as effective, so experts believe this may explain why people, over time, sleep deprived, can get a little crazy.
We wake up without realizing it
Scientific studies have shown that people wake up many times during their sleep - it sounds strange, of course, but it is true. These awakenings are so brief that we do not remember them. They usually occur during the transition between at different stages sleep.
Breathing may stop during sleep
Millions of people around the world suffer from a disorder known as sleep apnea. The disorder is characterized by pauses in breathing or episodes of shallow breathing during sleep. Each pause can last from several seconds to several minutes.
A person can hear explosions
Exploding head syndrome is a rare, benign condition in which a person hears loud noise imagines noises (such as a bomb exploding, a gunshot, hitting a musical cymbal, etc.) or experiences a sensation like an explosion when falling asleep or waking up. It is painless, but frightening to the one who suffers from it.
A person can talk in his sleep
Sleep talking is a parasomnia that refers to talking out loud while sleeping. It can be quite loud, ranging from muttering sounds to screams and long, often slurred speeches. This can happen repeatedly during sleep.
Pain threshold rises
When a person's body is completely relaxed to the point of paralysis, the nerves are unable to receive pain signals and transmit these signals to the brain. This also explains why we cannot hear, smell, see or feel while we sleep.
There are many reasons why sleep is the most favorite activity of many people.
This quiet part of our day is vital to both our physical and mental health.
Quite often we tend to think of sleep as a very inactive and quiet activity.
You will be surprised at how much happens in our bodies while we sleep.
However, there is nothing to worry about.
All the processes that occur are completely normal, they help our body function properly when we wake up.
Since lack of sleep can have devastating effects on a person's health in the long term, it is important to understand and appreciate its importance.
After all, we spend a third of our lives sleeping.
Therefore, our post today, talking about the things that happen in our body while we sleep, will help you better understand your body.
● 25. Body temperature drops
Because most of the body's muscles become inactive during sleep, the body burns fewer calories than when awake, so body temperature drops.
Scientists have found that the lowest body temperature in a person during sleep is at 02:30.
● 24. Eyes move
Although closed by eyelids, the eyes move in sleep.
Their movements even differ depending on the stage of sleep.
At first they roll smoothly, and then, when a person falls into deep sleep, they begin to move quickly.
However, a person, as a rule, does not remember this.
● 23. The body twitches convulsively
Sudden twitches and jerks are most often associated with the first stages of sleep.
They are generally harmless, but can be quite strong - sometimes to the point of actually waking you up.
● 22. Muscles are paralyzed
There is a compelling reason why most muscles become paralyzed during sleep: if they were active, a person could act while asleep, and this, of course, would be extremely dangerous.
● 21. Skin repairs itself
The top layer of skin is made up of compacted dead cells that are shed throughout the day.
During sleep, the skin's metabolic rate increases and many cells in the body exhibit increased production and decreased breakdown of proteins.
Because proteins are essential for cell growth and repair of skin damage from factors such as UV rays, deep sleep can truly be called "beauty sleep."
● 20. The brain forgets unnecessary information
“We take in a lot of information throughout the day, and fortunately most of it is forgotten,” says sleep specialist Christopher Colwell of the UCLA School of Medicine.
“If you remember everything you learned or heard all day, then the brain, in order not to become overloaded with information, will begin the sorting process during sleep, weeding out what is unnecessary.”
● 19. Throat narrows
Unlike most other muscles, the throat muscles are not paralyzed during sleep because they are needed for breathing.
However, they become more relaxed, causing the throat to narrow.
It also likely contributes to snoring.
● 18. The body produces hormones
During the slow-wave sleep phase, the human body produces growth hormones that stimulate cell growth, reproduction and regeneration.
Sleep, even if it is during the day, promotes the release of prolactin, an important regulator of the immune system.
● 17. The immune system is at its peak
Lack of sleep has been shown to affect the immune system.
One study found that people who were given a flu shot and deprived of sleep the next night were unable to produce the antibodies needed to protect against the flu.
Therefore, as soon as a person experiences the first signs of infection, one should sleep just enough for the immune system to fight the disease.
● 16. A person loses weight
During sleep, a person loses fluid by sweating and exhaling moist air.
This happens throughout the day, but drinking and eating will negate any weight loss.
Therefore, quality and long sleep is necessary for any diet to achieve success.
● 15. My mouth becomes dry.
Since saliva is mainly needed for the feeding process, and a person does not eat during sleep, the salivary flow at night is reduced.
Consequently, a person may feel dry mouth and thirsty when waking up in the morning.
● 14. A person can grind his teeth
It is estimated that around 5% of people suffer from a strange condition known as bruxism.
This parafunctional activity manifests itself in excessive grinding of the teeth and can ultimately lead to tooth damage.
Scientists aren't sure what exactly causes this condition, but they think it may be a form of stress relief.
● 13. The body lengthens
It has been found that people can be several centimeters taller in the morning than they were the night before.
When sleeping in a horizontal position, the spine is stretched because the weight of the body does not press on it from above.
● 12. Blood pressure decreases
During sleep, a person experiences what is called a "night dip" in blood pressure.
● 11. A person can walk in his sleep
Scientifically known as parasomnia, sleepwalking and other sleep activities involve behaviors, emotions, sensations, and dreams that typically occur during transitions between certain stages of sleep.
Parasomnia is mostly harmless, but there have been cases where people have been injured while sleepwalking.
● 10. A person can become sexually aroused
Both men and women can become sexually aroused in their sleep.
Because the brain is more active during sleep, it requires more oxygen.
As a result, blood flow throughout the body increases, causing the genitals to swell.
● 9. We dream
The content and purpose of dreams are not fully understood, but it is known that the average person sees 3-5 dreams per night.
We mostly see dreams in the first phase of sleep, when our brain is more active.
However, we forget most dreams immediately and quickly.
● 8. The brain makes decisions
Recent research has shown that the brain can process information and prepare for activities during sleep, effectively making decisions while unconscious.
In fact, our brain can even make important conclusions and discoveries while we sleep.
● 7. Oh, this flatulence
It’s unlikely that anyone will be happy to know this, but at night, the anal sphincter muscles relax slightly, releasing gases accumulated in the intestines.
The good news is that while you're sleeping, your sense of smell isn't as acute as when you're awake, so the release of gas at night tends to go unnoticed.
● 6. The body is completely cleansed of toxins
Removing toxins allows our body and brain to recover.
In poor sleepers, filtration is not as effective, so experts think this may explain why people who are sleep deprived for long periods of time can become a little crazy.
● 5. We wake up without realizing it
Scientific studies have shown that people wake up many times during their sleep - it sounds strange, of course, but it is true.
These awakenings are so brief that we do not remember them.
They usually occur during the transition between different stages of sleep.
● 4. Breathing may stop during sleep
Millions of people around the world suffer from a disorder known as sleep apnea.
The disorder is characterized by pauses in breathing or episodes of shallow breathing during sleep.
Each pause can last from several seconds to several minutes.
● 3. People can hear explosions
Exploding head syndrome is a rare, benign condition in which a person hears loud, imaginary noises (such as a bomb exploding, a gunshot, hitting a cymbal, etc.) or experiences an explosion-like sensation when falling asleep or waking up.
It is painless, but frightening to the one who suffers from it.
● 2. A person can talk in his sleep
Sleep talking is a parasomnia that refers to talking out loud while sleeping.
It can be quite loud, ranging from muttering sounds to screams and long, often slurred speeches.
This can happen repeatedly during sleep.
● 1. Pain threshold increases
When a person's body is completely relaxed to the point of paralysis, the nerves are unable to receive pain signals and transmit these signals to the brain.
This also explains why we cannot hear, smell, see or feel while we sleep.