The ratio and duration of the phases of slow and fast sleep in a healthy person. Sleep phases, sleep cycles, how much sleep you need, and whether you can get enough sleep The meaning of fast and slow sleep

During sleep, an adult alternates between 2 main phases: rapid and slow-wave sleep. At the very beginning after falling asleep, the duration of slow phase, and before waking up, the duration of slow-wave sleep is shortened, and the duration of REM sleep is lengthened.

A healthy adult begins sleep from the 1st stage. slow sleep, lasting 5-10 minutes. Next 2nd st. lasts 20 minutes. Then follow 3-4 tbsp., continuing for another 30-45 minutes. Then the sleeper again plunges into the 2nd art. slow wave sleep, followed by the first episode of REM sleep, which takes only 5 minutes. This is one cycle.

The initial cycle lasts approximately one and a half hours. During repetitions of cycles, the share of slow-wave sleep is shortened, and the share of fast sleep is lengthened. During the last cycle the duration fast cycle can reach one hour. A healthy adult experiences 5 sleep cycles during the night.

slow sleep

NREM sleep is also divided into certain stages:

1. The first is drowsiness with half-asleep visions. At this time, solutions to the day's problems may clearly appear in the brain.
2. The second is the so-called sleep spindles. At this time, consciousness turns off, but the person can be easily awakened due to increased perception thresholds.
3. The third is deeper sleep, in which sleep spindles are still preserved.
4. The fourth is the deepest sleep, which is sometimes called delta sleep. The duration of the deep sleep phase decreases from cycle to cycle.

Actually, the concept of delta sleep sometimes combines the penultimate and last stages. It is almost impossible to wake up a sleeping person during this period. This is precisely the stage in which nightmares, or nightmares, arise, but upon awakening the person does not retain memories of what happened. Normally, all 4 slow-wave stages of sleep of the 1st cycle occupy up to 80% of all sleep.

From the point of view, in this phase the body heals physically - cells and tissues are restored, self-healing occurs internal organs. During this period, the body restores its energy costs. During REM sleep, he restores his mental and intellectual resources.

What happens during delta sleep

During delta sleep, heart rate and breathing rates decrease, and all muscles relax. As this phase deepens, the number of movements in the sleeper becomes minimal, and it becomes difficult to wake him up. If you wake up the sleeping person at this time, he will not remember his dreams.

During slow-wave sleep, according to researchers of the phenomenon, restorative metabolic processes occur in tissues aimed at compensating for the catabolism that occurs during wakefulness.

Certain facts support this hypothesis. The delta sleep stage is prolonged in some cases:

• after active physical work;
• during a period of rapid weight loss;
• with thyrotoxicosis.

If subjects are deprived of this phase artificially (by exposure to sound, for example), then they begin to complain of physical weakness and unpleasant muscle sensations.

Delta sleep also plays an important role in memorization processes. Experiments were conducted during which subjects were asked to memorize meaningless combinations of letters before going to bed. After three hours of sleep, they were woken up and asked to repeat what they had learned before going to bed. It turned out that the more delta waves were recorded during this period of sleep, the more accurate the memories were. The results of these experiments determined that the memory deterioration that is observed with prolonged sleep disturbances and insomnia is associated specifically with problems in deep sleep.

The experimental subjects react to deprivation of deep sleep in the same way as to complete sleep deprivation: 2-3 nights with the use of stimulation reduce performance, slow down the speed of reactions, and give a feeling of fatigue.

How long should deep sleep last?

Each person has their own individual norm for how much sleep they need. There are short sleepers, medium sleepers, and long sleepers. Napoleon was a short sleeper - he slept only 4 hours. And Einstein was a long sleeper - his sleep norm was at least 10 hours. And both were very effective figures. However, if a common person forced to reduce his quota, then he will probably be negative in the morning, immediately tired and angry.

Scientists at the University of Surrey conducted an experiment in which 110 healthy adults who had never experienced sleep problems took part. On the first night, participants spent 8 hours in bed and showed that: subjects aged 20-30 years slept 7.23 hours, 40-55 years old 6.83 hours, 66-83 years old - 6.51 hours. The same trend was observed for the time of deep sleep: 118.4 minutes in the first group, 85.3 in the middle group, 84.2 minutes in the oldest group.

The first thing that begins to suffer with a lack of delta sleep is the endocrine system. If there is a lack of deep sleep, a person does not produce growth hormone. As a result, the belly begins to grow. These people suffer from apnea syndrome: at night they experience short-term breathing stops, during which they may simply not breathe for up to 1.5 minutes. Then, out of a sense of self-preservation, the body gives the command to wake up and the person snores. This is a very dangerous condition, during which heart attacks and strokes occur much more often. When treating the syndrome, people lose weight sharply because their hormone production improves. Sleep apnea causes irresistible daytime sleepiness, which is extremely dangerous if a person is driving at the time.

The norm for deep sleep in adults is from 30 to 70% of total sleep time. To increase its percentage you need to:

• create a more efficient wake/sleep schedule (you need to go to bed and get up at the same time);
• give the body physical exercise a couple of hours before bedtime (read more);
• do not smoke, do not overeat, do not drink coffee, alcohol, energy drinks before bed (we compiled);
• sleep in a comfortable room (ventilated, in the absence of extraneous sounds and light).

With the onset of old age, the duration of slow-wave sleep decreases. In 80 year olds long phase sleep becomes 62% less than twenty-year-olds. There are many factors that influence aging, but if the slow-wave sleep phase is also shortened, the aging process goes even faster.

How to measure your sleep

All 5 stages of sleep can be accurately divided only by the brain encephalogram, rapid eye movements, etc. modern research. If you just need to even out your sleep during the week, you can use special fitness bracelets. Fitness bracelets cannot read what phase of sleep you are in this moment the body is located, but they record the movements of a person in a dream. A fitness bracelet will help divide sleep into 2 phases - a person tosses and turns (phase 1-3), sleeps motionless (phase 3-5). The information on the bracelet is displayed in the form of a fence graph. True, the main purpose of this function of fitness bracelets is a smart alarm clock, which should gently wake up a person in the REM phase of sleep.

Discovery of delta sleep peptide

In the 70s, during experiments on rabbits, a group of Swiss scientists discovered the delta sleep peptide, which, when exposed to the brain, is capable of inducing this phase. Scientists isolated it from the blood of rabbits in deep sleep. The beneficial properties of the substance are gradually being revealed to people over the course of more than 40 years of research, it:

• activates stress defense mechanisms;
• slows down the aging process, which is facilitated by its antioxidant properties. The life expectancy of mice during experiments with its use increased by 24%;
• has anti-cancer properties: slows down the growth of tumors and suppresses metastasis;
• inhibits the development of alcohol dependence;
• exhibits anticonvulsant properties, helps reduce the duration of epileptic seizures;
• is an excellent pain reliever.

How to increase delta sleep time

A number of experiments have been carried out to study the influence physical activity on delta sleep. The men exercised on an exercise bike for two hours. Daytime activities had no effect on sleep duration. Evening classes had a noticeable impact:

• total sleep length increased by 36 minutes;
• the period of falling asleep and dozing has been shortened;
• delta sleep deepened;
• the cycle lengthened from one and a half to two hours.

With the introduction of additional intellectual loads (tests in the evening, solution logical problems), changes were also recorded in the deep sleep phase:

• the proportion of the deepest stage increased due to sleep spindles;
• 2nd cycle lengthened;
• an increase in the functioning of the activating systems was recorded.

Any stressful situations cause a shortening of the delta sleep phase. Delta sleep is an obligatory participant in all changes in human living conditions. Increasing its duration compensates for any load.

List of used literature:

• Feinberg I. Changes in sleep cycle patterns with age // J Psychiatr Res. - 1974 - Vol. 10, no. 3-4. - P. 283-306.
• Legramante J., Galante A. Sleep and hypertension: a challenge for the autonomic regulation of the cardiovascular system. // Circulation: journal. - 2005 - Vol. 112, no. 6 (9 August). - P. 786-8. - PMID 16087808.
• Morrissey M., Duntley S., Anch A., Nonneman R. Active sleep and its role in the prevention of apoptosis in the developing brain. // Med Hypotheses: journal. - 2004 - Vol. 62, no. 6. - P. 876-9.

Sleep is an unusual state of the body, which is sometimes compared to death. In fact, they have little in common. In contrast to the complete death of the body, rest, on the contrary, promotes long life. It renews all systems, helps restore physical and moral strength.

At the same time, sleep is not something homogeneous in structure. There are different phases, each of which performs a specific function and lasts a very specific amount of time. Everyone knows that deep sleep is beneficial. But when it occurs, how it affects the body - only a few know about it.

Sleep functions

While awake, people and animals spend a lot of energy. Sleep is one of the body’s self-regulation mechanisms that helps restore this energy. Its main functions are:

• rest nervous system;
• restoration of physical strength;
• “rebooting” the brain (at night the information received during the day is processed, systematized and stored);
• cleansing the body of toxic substances (it’s not for nothing that doctors recommend that sick people sleep more);
• restoration of immunity;
• cell renewal;
• an opportunity to wait out the period of darkness with benefit for the body.

Prolonged deep sleep helps improve memory, burn excess fat, overcome stress and illness.

What is the functional difference between deep and REM sleep?

During different phases, the brain processes information differently. REM and NREM sleep help you remember events that have happened and plan your future, but each in their own way.

The slow-wave sleep phase “switches on” memory resources. When a person falls into deep sleep (aka slow sleep), all the information received during the day begins to be systematized and “sorted out.” This phase improves memorization, logical thinking.

The REM sleep phase is a real “workshop” of the future. With its help, the brain simulates possible options development of expected events. It’s not for nothing that they say that you had a “prophetic” dream. In itself, of course, it is not prophetic. It’s just that during the period of REM sleep, a person developed models of the future, one of which he realized when he woke up. All this happens on a subconscious or intuitive level. However, human rest is not limited to these two phases. It has a more complex structure.

Phases and stages

There are 4 main stages of sleep:

1. Falling asleep.
2. Slow sleep.
3. Fast.
4. Awakening.

Each phase is characterized by a certain duration and accompanying physiological processes.

Falling asleep

1st phase - falling asleep. While a person falls asleep, his sensitivity decreases sensory systems and heart rate, consciousness gradually “turns off.” Even the glands begin to work less actively. This can be noticed by burning eyes and dry mouth. The approaching phase of falling asleep can be easily determined by obsessive yawning.

Night owls who stay up late reading or watching TV often notice such sensations. If all the described signs are present, it’s time to give the body a rest. The falling asleep phase is the shortest. It usually lasts about 10 minutes. Then slow-wave sleep begins, which in turn is divided into several stages.

What is slow wave sleep

Slow rest is a rest in which brain activity remains in the low amplitude range. Scientists record this using an EEG (electroencephalogram).

All phases of human sleep take different durations. If it takes 10 minutes to fall asleep, then the slow-wave sleep phase requires from 80 minutes to 1.5 hours. The duration depends on the individual characteristics of a person’s physiology, as well as on his rest regime. Unlike REM sleep, the NREM sleep phase is divided into several stages.

Stages

Slow wave (aka slow wave) sleep has the most complex structure. It is divided into the following 3 phases (or cycles):

Light sleep phase

It occurs immediately after falling asleep and lasts about half the time of slow sleep. At this stage, the person’s muscles completely relax, breathing becomes calm and deep. Body temperature drops slightly and heart rate slows down. The brain completely goes into rest mode.

Read also on the topic

Duration and characteristics of sleep phases in a child of the first year of life: norms of night and daytime rest for infants

The EEG records sleep spindles at this time. This is what scientists called theta waves, which form the sigma rhythm (12-14-20 Hz). Such brain activity indicates a complete shutdown of consciousness.

At this time, the person’s eyes do not move. He is completely relaxed, but not very deeply asleep yet. In easy time It is easy to wake a person from sleep. Loud sounds or physical impact can return him to a state of wakefulness.

NREM sleep phase

At that time brain activity is expressed in the production of delta waves, the frequency of which is 2 Hz. This is the calmest and slowest mode.

It takes about half an hour. During this phase of slow-wave sleep, a person sometimes experiences dreams.

Deep sleep phase

At this time, a person sleeps deeply and soundly. The EEG is dominated by delta wave oscillations with a frequency of 2 Hz. NREM and deep sleep are often combined under the umbrella term delta wave sleep. The duration of the deep sleep phase takes up approximately 15% of the entire night's rest.

The duration and features of the deep rest phase have been closely studied by specialists for a long time. It was found that at this time the brain actively produces dreams (about 80% of all visions that a person has during the night). Dreams appear in the form of pleasant images or nightmares. Most of them a person forgets when he wakes up.

Even though the deep sleep stage does not take very long, it has a profound effect on the body. For example, in young children suffering from enuresis, involuntary urination may occur at this time. In persons prone to sleepwalking, it is at this stage that attacks of this disease can occur.

REM sleep stage

This phase was discovered not so long ago (in 1953) and is still being comprehensively studied. It was found that the condition quick rest follows immediately after the deep one and lasts about 10-15 minutes.

REM sleep is the time when brain activity is expressed in the production of waves close in frequency to beta waves. Fluctuations in brain activity during this period are very intense and fast. Hence the name - “fast”. Also, this period in the scientific literature is called the REM phase, or REM sleep.

A person in this stage is completely motionless. His muscle tone drops sharply, but his brain activity is close to a state of wakefulness. Eyeballs move under closed eyelids.

The connection between vivid, memorable dreams and this phase is the clearest. While staying in it, a person sees the most colorful images and scenes. If awakening is initiated during REM sleep, in 90% of cases the person will be able to retell his visions.

Scientists cannot give a clear answer to the question of how long this sleep phase lasts. Its duration is approximately equal to 20-25% of the total time of night rest. The phase of REM, like slow-wave sleep, has a cyclical structure. The cycles are similar in the nature of brain activity, but differ in duration.

The first cycle occurs approximately 1.5 hours after falling asleep. The time of the next one increases a little and so on. In the morning, the duration of the last phase of REM sleep can reach several tens of minutes. In this case, the person sleeps shallowly until he finally wakes up completely.

As morning approaches, all systems in the body become active. Begins to work more actively hormonal system. Men have an erection of the penis, women have an erection of the clitoris. Respiration and heart rate changes. Alternate rises and falls in blood pressure alternate.

Waking up in different phases and rest cycles

General health and a person’s well-being directly depend on the quality and duration of night’s rest, which has a heterogeneous structure. Overnight, the human brain needs to go through the stages described. Only under this condition will the body fully recover.

Moreover, all phases are equally important. Slow, fast, deep sleep - they all perform important functions. Having learned what human deep sleep is, scientists have found that it is necessary for normal mental activity and the preservation of skills acquired throughout the day. Fast regulates energy resources. Its absence can lead to the death of the body.

Contents of the article

A third of human life is spent sleeping. This is a complex and necessary process for health. Deprivation of night rest for just 3 days can lead to disruption of many functions - loss of appetite, apathy. Recover at night physical strength, immunity is strengthened, brain activity changes, daily information is taken into account. To perform all these functions, a person goes through phases of rapid and slow sleep during the night.

Physiology of sleep

During the night, the phases of slow and fast sleep alternate more than once. First comes the slow one, then comes the fast one. Each has its own goals. During slow organism resting. When the fast phase begins, the body prepares to wake up, the heart begins to work actively, blood pressure increases, and vivid dreams occur.

The phases of slow and fast sleep are contained in a single cycle. It lasts from one and a half to two hours. For the whole night physiological standards 4 to 6 cycles should occur, then the person will wake up with the feeling that he has slept, rested, and gained strength.

In each subsequent cycle, the duration of the slow phase is shorter, and the duration of the fast phase is longer. In order for the full restoration of all systems to go well, you need to complete the cycles before 4 a.m. (for this you need to go to bed at about 10 p.m. the previous day). After this, the person will continue to sleep, but without the slow phase, because the recovery processes have already passed. It is better to wake up after the fast phase, as all systems are activated and ready to start working.

Although during the slow stage the speed of many physiological processes decreases, protein synthesis accelerates and hormones are produced. Sweating increases, blood supply to the brain increases, hair and nail plates continue to grow. During the slow phase, tissue and organ restoration actively occurs.

The fast phase is also necessary for the body. It allows a person to experience the emotions of those events that happened in life. This makes it possible for a person not to change over time, to remain emotionally stable, and to adapt to a changing world. For newborn children, the fast phase helps the rapid development of the brain and strengthens it with special impulses. This lasts until the age of two, then personality formation occurs.

Numerous examinations help to understand what slow and fast sleep is, the most common of which are tomography, electroencephalography, ultrasound studies, and others. modern techniques studying.

Alternation of stages

During NREM and REM sleep, the following are performed: different functions. Throughout the entire cycle, there are five stages with their own physiological characteristics:

• Stage 1 – takes 4-5% of the time, light sleep, the process of basic actions in the body slows down, blood pressure decreases;
• Stage 2 – 45-55%, there is a decrease in body temperature, slowing of breathing, decreased heart rate;
• Stage 3 – from 4 to 6% of the time, the beginning of deep, sound sleep;
• Stage 4 – 12 – 15%, rhythmic, unhurried breathing is observed;
• Stage 5 – 20 – 25% of the time, a person dreams peaceful dreams, the brain relaxes, the heartbeat quickens.

It takes from 15 to 40 minutes to fall asleep. If this takes 1 hour, then this is a sign of insomnia, which means it is necessary to take measures to eliminate it. The first cycle, that is, alternating slow and fast sleep, takes 1 hour, then the slow phase of another cycle begins again. Each time the sleep will be deeper. In the ratio of fast and slow sleep, the latter remains up to 80% of the total night time.

After passing through all the cycles, awakening occurs. It usually takes up to 3 minutes. During this time, consciousness is connected.

The alternation of stages does not change in a healthy person. The following factors can disrupt the sequence:

• emotional instability;
• age-related changes;
• prolonged stress, depression;
• mental disorders;
• long-term chronic diseases;
• injuries.

These disorders require treatment, as they can lead to complications. Deficiency of night rest or certain stages leads to the appearance of serious diseases.

The main differences between NREM and REM sleep

When comparing, it is difficult to answer which sleep is better - fast or slow sleep. Each phase performs its own function and is therefore needed by the body. The comparison is presented in the table, where slow and fast sleep are analyzed according to individual parameters.

Sleep characteristics	Slow	Fast
Vegetative system	There is a rapid, enhanced synthesis of hormones produced by the pituitary gland of the brain. Active growth of nails, eyelashes, hair, bones.	The heartbeat quickens, breathing becomes deeper and more active, and the pupils move faster.
Dreams	I rarely have dreams. But if this happens, then the dreams are characterized by calm content without temperamental turns.	Dreams with vivid storylines, intense experiences, strong emotions and color effects.
Subtleties of breathing	It can be rare, superficial, deep, there may be no rhythm, which occurs in the delta stage.	Uneven, sometimes delayed, frequent. This is how the reaction to dreams manifests itself.
Awakening	Upon waking up, a person feels tired and depressed. The sprinkling process will be difficult. This is the result of incomplete processes in the slow phase of sleep.	He wakes up easily, on his own. You feel freshness, vivacity, energy.
Brain temperature	Decreases.	Increased due to the influx of plasma and enhanced metabolic processes.
Eye movement	Smooth, leisurely, lasting until the end of this phase.	There is continuous, chaotic movement.

The stages of REM and NREM sleep differ from each other, but are mutually dependent and in harmony. They are equal in importance and take part in the single action of rest and restoration.

Main stages of slow-wave sleep

When falling asleep, a person finds himself immersed in a slow phase. It received this name because of the leisurely movement of the pupils at this stage. In this phase, all natural processes in the body calm down. Blood pressure decreases, the brain begins to rest, relaxes, and the heartbeat becomes less frequent.

The night's rest cycle consists of four stages slow-wave sleep and two stages of fast sleep. With the onset of night, slow-wave sleep has an advantage; towards the end of the rest, the share of fast sleep increases.

Wakefulness - NREM sleep (stages 1 and 2) - Delta sleep (stages 3 and 4) - REM sleep

In slow-wave sleep there are stages of drowsiness, then there are “sleep spindles”, then delta sleep follows. Real deep sleep will be observed during the deep delta sleep stage. These stages differ from each other in physiological parameters and actions occurring in the body.

When falling asleep, physiological categories change. The heartbeat decreases, blood pressure decreases, and blood moves more slowly through the vessels. When the last stage is reached, the heartbeat becomes faster and blood pressure begins to rise. At the same time, the body prepares to move on to the next fast phase. During the slow-wave sleep stage, the events of the past day are replayed in the memory, so a special rhythm of breathing and twitching of the limbs is possible.

During deep sleep, damaged cells are restored, which is why this stage is so important for maintaining youth and healing.

For an adult, the norm for slow-wave sleep is 118 minutes per night.

IN difficult situations The body independently prolongs this stage. So a person who adheres to a strict diet will feel weak and begin to sleep a lot. This body requires more time to recover. This happens in diseases of the thyroid gland, in professional athletes, and in people engaged in heavy physical labor.

The norm of deep sleep in adults should not be disturbed. If you don't get enough sleep, it will be difficult to compensate for the deficit in the slow stage of sleep. The shortage will constantly accumulate and negatively affect well-being and performance. With a prolonged disruption in the sleep schedule, for example, during a night work schedule, disturbances in the endocrine system begin. Growth hormone stops being produced, which means that a person’s fat layer on the stomach. Tissues cease to renew themselves steadily, new pathologies develop, and chronic diseases worsen.

Nap

The first stage is the slow phase, lasts up to 10 minutes. In this case, slow movements of the pupils under closed eyelids are noted. The body is in a soft, sleepy state, in which the physiological indicators of pulse, respiration, and pressure decrease. But it’s still easy to wake a person up. The brain is not resting yet, but is actively working. In this state, you can find answers to unsolvable problems. One has only to remember about them. In the morning it will not be possible to restore the chain of decisions, but the conclusion will remain in memory. If you constantly wake a person up during the slow phase, he will gradually become irritable and nervous.

Sleepy spindles

This stage lasts up to 20 minutes. It got its name from the characteristic pattern on the EEG graph. The heart rate slows down, muscle activity decreases, and the reaction to external stimuli remains. A person can wake up from a small, extraneous noise. For example, crying small child Mom will hear. Regular awakenings at the sleep spindle stage lead to scattered attention.

Delta

The stage lasts from 10 to 15 minutes. There is a gradual decrease in blood pressure, loss of consciousness, shallow, slow breathing. Most people don't dream, but people with depression may have nightmares. Data is transferred from short-term to long-term memory. At constant lack of sleep There is an increase in errors in mathematical calculations, a decrease in memory, reaction and speed of thinking.

Deep delta sleep

This stage lasts from 25 to 40 minutes. Represents real sound deep sleep. There is no reaction to odors or other external stimuli. At this time, it is difficult to wake up a person; you need to shake him by the shoulders and loudly call him by name. During sleep, metabolism is restored and renewed at the cellular level. There are calm dreams, manifestations of sleepwalking and sleep talking are possible in people prone to such pathologies.

According to scientists, the less delta sleep, the faster the body aging. To increase the duration of this stage, you must follow the following rules:

• before going to bed at night, take walks or perform simple physical exercises;
• correctly alternate work and rest;
• do not overeat in the evening, do not drink alcohol, caffeinated drinks, or energy drinks;
• sleep in a ventilated room, preferably in darkness and silence.

By increasing the deep phase of delta sleep, it will be possible to fully restore cells. This will have a positive effect on your appearance. First of all, this will affect the condition of the skin. Good dream affects the smoothing of wrinkles, a healthy skin tone is acquired, and puffiness under the eyes goes away.

Fast cycle its features

Dreams that occur during the fast phase are remembered very well

During REM sleep, unusual actions begin; it is no coincidence that it is called the paradoxical cycle. Scientists do not fully understand the significance of this night phase cycle for humans. If during the slow stage there is active recovery, then in the fast phase other processes take place.

The pupils move chaotically under closed eyelids, as if they are watching some events. All indicators of a person (muscle tone, brain activity, blood pressure, heartbeat) indicate that he is awake, only his consciousness is turned off. A person often participates in his dreams. When he is woken up during the rapid phase, he remembers small details and talks about everything in detail and with emotion.

During this period, hormonal changes occur. The functioning of the organs is being adjusted endocrine system. In the fast phase, the genital area is adjusted. During this stage, nocturnal erections, wet dreams, and orgasms occur, even in the absence of erotic dreams. Often heart attacks and strokes also occur at this time. A relaxed heart and blood vessels receive a huge load and cannot cope with it.

2 cycles included in the fast stage:

• unemotional;
• emotional.

They change each other throughout the night. The emotional cycle is always longer. During the fast period, daily information and data are processed, the brain adapts to the changing situation. People who do not have the opportunity to get a good night's sleep during this phase lose the ability to restore mental protection. Over time, they become irritable, whiny, absent-minded, and develop nervous disorders.

Features of awakening in each phase of sleep

Vigor and ability to work in the first half of the working day depend on the person’s awakening. If this happened from external irritating phenomena (a sharp ringing of an alarm clock, a scream, a jolt, a bright flash of light), then a certain time is needed to put the body in order. Some people do not even realize after such an awakening where they are, what they need to do. It is difficult for people with chronic low blood pressure. They are forced to accept medicines after such a morning rise.

When you wake up on your own in the fast phase, you have a chance to feel cheerful and fresh even early in the morning. The body is ready to work, all that remains is to turn on the consciousness. A person remembers his dreams and can retell them in detail.

It is important to consider the subtleties of awakening in different phases so as not to feel overwhelmed and unable to work. A good invention for taking into account the stages of sleep is “”. They are able to read the body’s readings, determine the necessary phases of REM sleep, and send a signal to wake up at exactly this time. The disadvantage of this device is the likelihood of hearing the call ahead of schedule. The alarm clock performs its functions ahead of schedule.

Smart alarm clock will help you wake up on time

We have invented a special calculator that helps calculate the phases of a person’s night rest by defining algorithms. You just need to enter your bedtime time, the program will perform the full calculation. A time will be determined when you need to get up in order to feel freshness, strength and vigor.

It is better to calculate the time of awakening through experiment. Determine the time of the fast phase, wake up and determine whether it is easy to get up, whether there is cheerfulness and activity. If you liked the sensations, then you should try to maintain this regime, it is optimal for this age and type of activity. The slow stage takes about 120 minutes, the fast stage lasts 20 minutes. After falling asleep, 4 cycles must pass to complete recovery and final awakening. If you go to bed at 22 o'clock, then 4 cycles will pass from 4:40 to 5:00. If it is too early to get up, then the next cycle will end from 7:00 to 7:20.

The time you fall asleep matters. The optimal time interval is from 19 to 20 hours. Our ancestors went to bed around this time, with the end of daylight. With the invention of electricity, life changed. People began to go on vacation much later. This has increased the number of neurological diseases, chronic fatigue, depression, oncology.

The best time to wake up will be the first or second stage after the end of the fast phase. It is important to wake up and get up and not doze off a little more. In this case it will begin new cycle, will go again slow stage, during which it is difficult to wake up, there will be no former vigor. REM sleep is different from slow sleep, but it is better to wake up on your own when the body is ready for it.

You can go out onto the balcony with coffee - it will wake you up / Photo nickned.livejournal.com

In order not to fall asleep again after waking up, you can have a snack to finally restore consciousness. It is useful to go for a walk or to the balcony. The morning air will invigorate you, you will have strength and vigor for a new day. After 3-4 days of such a rise, the body will get used to getting up without getting enough sleep, which only spoils the morning awakening.

For supporting good health, good appearance requires REM and NREM sleep. They have a mutual influence on the human body. One should not intrude unnecessarily into the well-established structure of nightly recovery. On the part of a person it is required to maintain the correct night sleep, avoid frequent lack of sleep, interruption of sleep in in the wrong place. Following the rules for night rest will help you maintain your health for a long time.

Is physiological process, in which a person (as well as mammals, fish, birds and some insects) is in a state radically different from the waking state. This condition characterized by altered consciousness, a decrease in the level of brain activity and reactions to external stimuli. Natural sleep differs significantly from such similar states as coma, suspended animation, fainting, sleep under the influence of hypnosis and Sopor. Along with sleep in the usual sense of the word (i.e. sleep at night), certain cultures allow the existence of the so-called daytime rest or siesta. Short-term nap is part of the traditions of many peoples. According to the results of ongoing research, regular afternoon naps can significantly reduce (by almost 40%) the risk of a heart attack. In a word, sleep is the most important element human life and at the suggestion of researchers, since 2008, every 3rd Friday of the first month of spring is celebrated as Sleep Day.

Basic functions of sleep

Thanks to sleep, the body receives the necessary rest. During sleep, the brain processes the information accumulated during the day. The so-called slow sleep allows you to better assimilate the studied material and consolidate it in memory. REM sleep provides the ability to simulate upcoming events at the subconscious level. Important function sleep is also restoration immune system human by activating the activity of T-lymphocytes, which resist viral infections and fight colds.

Physiology of the sleep process

Healthy sleep can last from 4 to 8 hours. However, these indicators are quite subjective, since the duration of sleep depends on physical fatigue person. A significant amount of work done during the day may require a longer night's rest. Normal sleep is cyclical and is required by the human body at least once a day. Sleep cycles are called circadian rhythms. Every 24 hours, circadian rhythms are redefined. The most important factor during sleep, illumination is considered. The concentration of photodependent proteins in the body depends on its natural cycle. Usually, circadian cycle correlates with the length of daylight hours. Just before sleep occurs, a person feels drowsy, his brain activity decreases, and there is also a change in consciousness. In addition, a person who is in a sleepy state has a decrease in sensory sensitivity, a reduction heart rate, yawning, and also a decrease in the secretory function of lacrimal and salivary glands. One more physiological feature sleep is a process called “vegetative storm”, i.e. when various forms of arrhythmias are observed, an increase or decrease in blood pressure, increased blood supply to the brain and secretion of the adrenal glands, erection of the clitoris and penis.

Structure of the sleep process

Any sleep is divided into several stages, which are repeated with a certain pattern throughout the night (naturally, provided that the daily schedule is absolutely normal). Each stage of sleep directly depends on the activity of one or another brain structure. The first stage of sleep is slow-wave sleep (Non-REM). The duration of Non-REM sleep is 5 to 10 minutes. This is followed by the second stage, lasting approximately 20 minutes. Over the next 30-45 minutes, another 3 and 4 stages of sleep are observed. Next, the person again falls into the second stage of slow-wave sleep, at the end of which rapid REM sleep occurs (episode 1). This is approximately 5 minutes. All of the above stages are the first sleep cycle, which lasts from 90 to 100 minutes. After this, the cycle repeats again, but at the same time the stages of slow-wave sleep are reduced, and REM sleep, on the contrary, increases. Typically, the last sleep cycle ends with an episode of REM sleep, lasting in some cases about 1 hour. Full sleep includes 5 full cycles. The sequence in which one stage of the sleep cycle follows another, as well as the duration of each cycle, is usually presented in the form of a hypnogram. The sleep cycle is regulated by certain areas of the cerebral cortex, as well as the locus coeruleus, located in its trunk.

What is slow wave sleep?

NREM sleep (also called orthodox sleep) lasts 80 to 90 minutes and occurs immediately after a person falls asleep. The formation and development of slow sleep is ensured by the anterior parts of the hypothalamus, raphe nuclei, nonspecific nuclei of the thalamus and the middle part of the pons (the so-called Moruzzi inhibitory center). At the first stage of slow-wave sleep, the alpha rhythm decreases, transforming into slow low-amplitude theta rhythms, equal in amplitude to the alpha rhythm or exceeding it. The person is in a state of drowsiness (half-asleep), and dream-like hallucinations are observed. Muscle activity decreases, heart rate and breathing decrease, metabolic processes slow down, and the eyeballs move slowly. At this stage of sleep, solutions to problems that seem unsolvable during wakefulness are intuitively formed. By at least, the illusion of their existence may arise. The first stage of slow-wave sleep may also include hypnogogic jerks.

In the second stage of Non-REM sleep (this is usually light and shallow sleep), a further reduction in muscle activity occurs, the heart rate slows down, body temperature drops, and the eyes become motionless. The second stage is approximately up to 55% of the total sleep time. The first episode of the second stage lasts approximately 20 minutes. The electroencephalogram shows at this moment the predominant theta rhythms and the emerging sigma rhythms (the so-called “sleep spindles”), which are essentially rapid alpha rhythms. At the moment of the appearance of sigma rhythms, consciousness turns off. However, during pauses between sigma rhythms, which occur at a frequency of 2 to 5 times per minute, a person can be easily awakened.

At the third stage of slow-wave sleep, the total number of delta rhythms is no more than 50%. At the fourth stage this figure exceeds 50%. The fourth stage is slow and deep sleep. Quite often stages III and IV are combined and called delta sleep. It is extremely difficult to wake a person during delta sleep. Dreams usually appear at this stage (up to 80%). A person may begin to talk, sleepwalking is possible, nightmares may occur and enuresis may develop. At the same time, a person usually does not remember any of the above. The third stage lasts from 5 to 8% of the total sleep time, and the fourth stage takes from 10 to 15% of the entire sleep period. The first four stages of slow-wave sleep normal person last from 75 to 80% of the total duration of this physiological process. According to researchers, Non-REM sleep provides full recovery energy expended per day. In addition, the slow-wave sleep phase allows you to record conscious memories of a declarative nature in your memory.

What is REM sleep?

Rapid eye movement sleep is also called REM sleep, paradoxical sleep, or rapid wave sleep. In addition, the generally accepted name is the REM (rapid eye movement) stage. The REM stage lasts 10 to 15 minutes and follows non-REM sleep. REM sleep was discovered in 1953. The centers responsible for REM sleep are: the superior colliculus and the reticular formation of the midbrain, the locus coeruleus, as well as the nuclei (vestibular) medulla oblongata. If you look at the electroencephalogram at this moment, you can see quite active fluctuations in electrical activity, the values ​​of which are as close as possible to beta waves. During REM sleep, the electrical activity of the brain is almost identical to the waking state. However, at this stage the person is completely motionless, since his muscle tone is zero. At the same time, the eyeballs actively move under closed eyelids, moving quickly with a certain periodicity. If you wake up a person in the REM stage, there is a 90% chance that he will report an exciting and vivid dream.

As noted above, the electroencephalogram of REM sleep reflects the activation of brain activity and is more reminiscent of the EEG of the first stage of sleep. The first episode of the REM stage lasts from 5 to 10 minutes and occurs 70-90 minutes after the person falls asleep. Throughout the entire sleep period, the duration of subsequent episodes of REM sleep becomes increasingly longer. The final episode of REM sleep can last up to 1 hour. The duration of REM sleep in a healthy adult is approximately 20-25% of the total sleep time. From one cycle to the next, the REM sleep phase becomes longer and longer, and the depth of sleep, on the contrary, decreases. Disturbances of slow-wave sleep are not as severe for the psyche as interruption of the REM phase. If any part of REM sleep is interrupted, it must be replenished in one of the subsequent cycles. Experiments conducted on mice have proven the detrimental effect of the missing REM phase on these mammals. After 40 days, the mouse deprived of REM sleep died, while the rodents deprived of slow-wave sleep continued to live.

There is a hypothesis that during the REM phase, the human brain works to organize the information received during the day. Another theory is that REM sleep is especially important for newborns, providing neural stimulation that promotes the formation and development of the nervous system.

Sleep duration

Duration normal sleep can vary from 6 to 8 hours per day. However, this does not exclude large deviations in one direction or another (4-10 hours). If sleep disturbances are observed, then its duration can be equal to several minutes or several days. When the duration of sleep is less than 5 hours, this is considered a violation of its structure, which can lead to the development of insomnia. If you deprive a person of sleep, then within a few days his consciousness will lose clarity of perception, an irresistible urge to sleep will appear, and “dips” into the so-called borderline state between sleep and wakefulness will be observed.

Dreams

Along with the corresponding physiological process, the word “sleep” also means a sequence of images that arise in the REM sleep phase and, in some cases, are remembered by a person. A dream is formed in the consciousness of a sleeping person, consisting of a variety of subjectively perceived tactile, visual, auditory and other images. Usually the person who is dreaming is not aware that he is in a dream state. As a result, the dream is perceived by him as an objective reality. An interesting type of dreams are considered lucid dreams, in which a person understands that he is dreaming, and therefore can control the development of the plot in a dream. It is believed that dreams are inherent in the REM sleep phase, which occurs once every 90-120 minutes. This phase is characterized by rapid movement eyeballs, increased heart rate and respiration, stimulation of the pons, as well as short-term relaxation of skeletal muscles. According to the results of recent research, dreams may also be characteristic of the slow-wave sleep phase. At the same time, they are less emotional and do not last as long as REM dreams.

Sleep pathologies

All kinds of sleep disorders are quite common. For example, the cause of insomnia (insomnia) can be psychosis, depression, neurosis, epilepsy, encephalitis and other diseases. Apnea is a breathing disorder of a sleeping person, the causes of which can be mechanical or psychogenic in nature. Parasomnias such as sleepwalking, nightmares, epilepsy and teeth grinding are formed and develop on the basis of neurosis. Pathologies such as lethargic sleep, narcolepsy and sleep paralysis are among the most severe disorders sleep. In case of any alarming factors associated with obvious deviations in the structure of sleep, you should seek help from a specialist.

Pharmacological hypnotics

Sleep regulation using pharmacological agents must be carried out under the supervision of a physician. Along with this, it should be remembered that long-term use sleeping pills reduces the effectiveness of the latter. Relatively recently, the group of sedatives even included drugs - morphine and opium. Barbiturates have also been used as sleeping pills for quite a long time. Melatonin is considered one of the most progressive drugs at the moment. No less effective treatment Insomnia is helped by taking magnesium supplements, which improve sleep and promote the production of melatonin.

Sleep Study

According to prominent researchers of the past and present, sleep plays a more important role for the human body than food. In the second half of the 20th century, technologies for recording the activity of muscles (EMG), brain (EEG) and eyes (EOG) were developed, after which it was possible to formulate ideas about the structure of sleep and its nature, which no one has yet refuted .

Adequate rest is one of the main components of human health. For the formation, development, normal functioning The body creates ideal conditions during sleep. Only during this period are beneficial hormones produced and amino acids are synthesized. There is also improvement, systematization of brain activity, and unloading of the nervous system.

To understand the processes taking place, you should study what slow and fast sleep is, what are the differences between these structural units and determine their importance for people. It is good to compare these parameters using indications from comparative tables.

Psychophysical processes occurring during sleep divide it into phases. At this time, different activity of the brain is observed, regeneration of certain organs and systems occurs.

REM sleep and slow-wave sleep have a certain relationship with each other. It changes with the transition from one cycle to the next. Constant interruption of one of the components has negative consequences.

Phase components of sleep and their order

Sleep is a definite structure; it includes several cycles that appear 4-5 times during the night. Each one is approximately 1.5 hours long. This form contains phases of slow and fast sleep.

An adult's rest begins with napping, which is the initial structural unit slow period. Next, three more components pass in turn. Then there comes a short period. The duration changes every cycle.

Features of slow sleep

The slow period lasts three-quarters of the entire rest period. After falling asleep, it is at its greatest length, gradually shortening in the morning.

During a long rest, 4-5 periods included in cycles occur; this is the optimal value. It begins the process of putting a person to sleep. At the third phase stage, attacks of sleepwalking may occur.

Structure

This phase is structured by periods. They all play great importance for a person. Each has its own characteristics, features, and functions change in the process.

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

The first period is characterized by slow eye movement, a decrease in temperature occurs, the pulse becomes less frequent, stabilization occurs nervous activity. It is at this moment that a solution to a problem that appeared during the day can come, the missing link in the semantic chain can be filled. Waking up is very easy.

In the second period, consciousness begins to switch off, the person sinks deeper into slumber. The pulse is rare, muscle relaxation occurs.

During the third stage, the heart begins to contract more frequently and more shallow respiratory oscillations occur. The flow of blood to the tissues is activated, eye movement occurs very slowly.

The last period is characterized by the greatest immersion. At such a moment, it is very difficult for people to wake up, they get up unrested, have difficulty integrating into the environment, dreams are not stored in memory. All body functions are significantly slowed down.

Signs

You can understand that a person is in the slow-wave sleep phase by comparing characteristic indicators: breathing, which becomes rare, shallow, often arrhythmic, the movement of the eyeballs first slows down, then completely disappears.

The heart rate slows down and the body temperature becomes lower. By this period, the muscles relax, the limbs do not move, and there is no physical activity.

Meaning

While in slow-wave sleep, internal organs are restored. During this time, growth hormone is released, this is especially important for children. They develop and improve all their systems over such a period.

It is important to know! During this period, substances necessary for the normal functioning of the body accumulate and amino acids are synthesized. This type of sleep is responsible for physiological rest.

Contradictions of paradoxical sleep

REM sleep is also called paradoxical because of its inconsistencies various manifestations internal processes. During this period of rest brain activity very active, it can be even higher than when awake, but at this time the person is in the process of dozing.

Muscle tone is significantly reduced, but the stage is characterized by movement of the eyeballs and twitching of the limbs. If such a rest for some reason takes a long time, upon awakening there is a feeling of exhaustion, snippets of dreams are spinning in the head.

Manifestations

The fact that a person is in the REM sleep phase can be noticed without the help of devices. There are a number of specific manifestations. These include:

Body temperature rises and heart rate increases. The brain begins to be active. During this period of rest, a unification occurs, a comparison of genetic information with acquired information occurs.

The value of the fast phase

During the period of rapid rest, the nervous system is activated. All acquired knowledge, information, relationships, and actions are processed and analyzed. Serotonin, the hormone of happiness, is produced.

During this period, the formation of the most important mental functions in children. Insufficient duration of such rest may mean the rapid appearance of problems with consciousness. Programs for future human behavior are created, answers to questions that cannot be found while awake are formulated.

Dreams

The dreams that come to a person during this phase are the most vivid and memorable. They are emotionally colored and dynamic. External stimuli can be intricately woven into the plot of a vision.

Visions are transformed into different symbols, images, and everyday reality. IN paradoxical phase Usually a person realizes that events are not happening in reality.

Awakening in different phases: differences

The structure of sleep is heterogeneous. All phases are distinguished by different brain activity, psychophysical activity, and regeneration of certain human systems.

It is important to know! The incompleteness of the processes causes a difficult transition to wakefulness in slow-wave sleep. When climbing quickly, the climb is easy, and the start of vigorous activity occurs without problems. But constant interruption of rest in this phase has a negative effect on the psyche.

Table: comparative characteristics of sleep phases

Parameters characterizing rapid and slow-wave sleep are shown comparison table. This is the basic data that helps to recognize the rest period. From one cycle to the next, the duration of the first becomes shorter, while the paradoxical one lengthens.

Indicators	Slow phase	Fast phase
Number of stages	4	1
Sleep depth	deep	surface
Having dreams	calm, poorly remembered	vivid, emotional, retained in memory
Eye movement	no or very slow	fast
Muscle tone	slightly reduced	sharply weakened
Breath	rare, stable	arrhythmic
Heartbeat	slowed down	accelerated
Body temperature	reduced	increased
Duration	75-80% rest	20-25% of sleep duration

Sleep Research: Interesting Facts

The paradox of time perception is often encountered in relation to sleep. There are times when it seems like you just closed your eyes, and several hours have already passed. The opposite also happens: it seems that you slept all night, but 30 minutes have passed.

It has been proven that the brain analyzes sounds, sorts them, and can weave them into a dream. Moreover, in some phases people can awaken if they are called by name in a whisper. The greater the biological age of a person, the shorter the duration of the paradoxical stage. In infants it exceeds the slow one.

A person spends a third of his life sleeping. If you sleep less than a quarter of a day for two weeks, the state of the body will correspond to being in drunkenness. Memory will deteriorate, concentration and reaction will suffer, and problems with coordination will arise. But many geniuses practiced polyphasic rest over a long period of time, the total duration of which was no more than half the norm. At the same time, they felt cheerful, their performance improved, and discoveries were made.

Absolutely all people see dreams, but almost all of them are forgotten. Animals also dream. Not so long ago most of humanity saw black and white dreams, and now 85% of men and women view vivid stories. The explanation for this is the creation of color television broadcasting.

Blind people are also not deprived of dreams. If the blindness is acquired, then the pictures represent what was previously seen. In congenital blindness, vision consists of sounds, smells, and sensations. They do not experience the phenomenon of rapidly moving eyes under their eyelids. These people are much more likely to have nightmares.

The longest period of wakefulness of a healthy person was the period of 11 days during which an American schoolboy did not sleep. After a head injury and brain damage, a Hungarian soldier did not take a nap for 40 years. At the same time, he felt cheerful, did not experience fatigue or discomfort.

It is important to know! Few girls who dream of a slim figure know the following fact. Systematic lack of sleep leads to excess weight gain. One of important conditions Losing weight is getting enough sleep.

Women's deep rest is often 20 minutes longer than men's, but the latter sleep more restlessly and wake up more often. The weaker sex complains more about sleep disturbances and gets less sleep. Ladies are more susceptible to emotionally strong visions and nightmares.

Conclusion

You can’t make a choice about whether fast or slow sleep is better. Both of these components must be present in a person’s rest without fail and in the correct percentage.