NREM and REM sleep. Fast and slow phases of sleep - characteristics and their effects on the human body Slow sleep duration

Sleep is such a simple daily action that a person performs in the evening and wakes up in the morning. Usually we don’t think about this question - what is sleep? However, sleep as a physiological action is not simple. Sleep consists of two phases: fast and slow sleep. If you deprive a person of the REM phase of sleep (wake him up at the beginning of this stage), then the person will experience mental disorders, and if you deprive him of the slow phase of sleep, then the development of apathy and depression is possible.

Phases and cycles of normal sleep, properties of fast and slow sleep

Characteristics of REM sleep

Let's start with fast sleep phases. This phase is also called paradoxical or phase rapid eye movements(REM sleep). This period of sleep is called paradoxical because electroencephalogram resembles that during wakefulness. That is, the α rhythm is recorded on the electroencephalogram; the curve itself is low-amplitude and high-frequency. Let's look at what an electroencephalogram is - it is a recording of brain signals using special equipment. Just as heart activity is recorded on a cardiogram, brain activity is also recorded on an encephalogram. But in this phase paradoxical sleep There is a more pronounced relaxation of skeletal muscles than in the slow-wave sleep phase. In parallel with the relaxation of the skeletal muscles, rapid eye movements are made. It is these rapid eye movements that give the name REM sleep. During the rapid phase of sleep, the following brain structures are activated: posterior hypothalamus (Hess center) - sleep activation center, reticular formation upper sections brain stem, mediators – catecholamines (acetylcholine). It is during this phase that a person dreams. Tachycardia, increased blood pressure, increased cerebral circulation. Such phenomena as somnambulism, sleepwalking, sleep-speaking (speech in a dream), etc. are also possible. It is more difficult to wake a person than in the slow phase of sleep. In total, REM sleep takes up 20–25% of total sleep time.

Characteristics of non-REM sleep phase

During the slow-wave sleep phase, the electroencephalogram contains sleep spindles. The following structures are involved in the implementation of this phase of sleep: the anterior hypothalamus and the lower parts of the reticular formation. In general, slow-wave sleep takes up 75–80% of the time. total number sleep. The mediators of this sleep phase are gamma-aminobutyric acid (GABA), serotonin, δ - sleep peptide.
The slow phase of sleep is divided into 4 subphases according to its depth:

• nap(falling into sleep). The electroencephalogram reveals α - waves, β and ζ. With insomnia, drowsiness is very pronounced, the remaining subphases of slow-wave sleep may not occur
• sleep spindle phase. The electroencephalogram shows predominantly ζ waves and sleep spindles. This is the longest phase of sleep - it takes up 50% of the total sleep time. A person comes out of this phase easily
• the third and fourth subphases of slow-wave sleep are combined into one under the general name δ – sleep(slow, deep). The third subphase represents the transition to this phase. It is very difficult to wake a person. This is where nightmares happen. With insomnia, this phase is not disturbed.

Sleep cycles

The phases of sleep are combined into cycles, that is, they alternate in strict sequence. One cycle lasts about two hours and includes slow-wave sleep, consisting of subphases, and REM sleep. Within these two hours, 20 - 25% is REM sleep, that is, about 20 minutes, and the rest of the time is NREM sleep. Normal starts healthy sleep from the slow phase. By morning, a person's REM sleep phase predominates, so it is often difficult to get up in the morning. Today, it is considered sufficient for proper rest to have 3-4 sleep cycles, that is, a sleep duration of 6-8 hours. However, this statement is only true for healthy people. Modern scientists have shown that with various somatic diseases, the need for sleep increases. If the quality of sleep suffers, then the person also wants to sleep more. Almost every person has experienced sleep quality problems at some point in their lives. Therefore, today the problem of sleep disorders is very relevant.

Types of sleep disorders

Doctors from almost all specialties encounter sleep disorders in their patients. Approximately half of the Russian population is dissatisfied with the quality of their sleep. In more prosperous countries, sleep disturbances of varying degrees affect between a third and half of the population. Sleep disorders occur in at different ages however, their frequency increases with age. There are also gender differences - sleep disturbances are more common in women than in men.

Sleep disorders are conventionally divided into three groups:

1. presomnia sleep disorders
2. intrasomnic sleep disorders
3. post-somnia sleep disorders

Complaints made by people with presomnia sleep disorders.
Can't sleep?

Let's take a closer look at what each group represents. First group – presomnia disorders. This group includes sleep disorders associated with difficulty falling asleep. In this case, various fears and anxieties come to the person’s mind, and he cannot fall asleep for hours. Often worries and fears about not being able to fall asleep appear even before going to bed. Worries and intrusive thought that tomorrow everything will happen again. However, if they manage to fall asleep, then these people sleep well.

Complaints made by people with intrasomnic sleep disorders.
Do you wake up at night?

The second group is the so-called intrasomnic disorders. This group combines sleep disorders in which the process of falling asleep is more or less satisfactory, but night awakenings occur due to various reasons. Such night awakenings are quite frequent, and after each of them it is not possible to fall asleep for a long time. As a result, you feel sleepy in the morning. Also, in the morning such people are not alert enough.

Complaints made by people with post-somnic sleep disorders.
Do you wake up early?

The third group is combined post-somnia disorders sleep. With this type of sleep disorder, sleep itself and the process of falling asleep are good, however, awakening occurs quite early. Such people usually say: “Well, there’s just no sleep in either eye!” As a rule, repeated attempts to fall asleep are unsuccessful. Thus, the time spent sleeping is reduced.

All these types of sleep disturbances lead to increased daytime fatigue, lethargy, fatigue, and decreased activity and performance. Added to these phenomena is a feeling of depression and bad mood. A number of ailments appear that are usually associated with sleep disturbances. These ailments are of a completely diverse nature and can affect the activity of all organs and systems.

What people with sleep disorders dissatisfy about their sleep??

Let's try to take a closer look at people who are worried about sleep disorders.

1. The first category is those who sleep little, but quite well. As a rule, this applies to young people with an active lifestyle. These people are often successful, or aspiring to succeed in some area. For them, this sleep pattern is not a pathology, but a way of life.

1. The second category is people who are dissatisfied with the quality of their sleep. They are embarrassed by insufficient depth of sleep, frequent episodes of awakening and a feeling of lack of sleep in the morning. Moreover, it is the quality of sleep, and not its duration, that worries this category of people.

1. The third category unites people who are dissatisfied with both the depth of sleep and the duration of sleep. That is, sleep disorders are deeper than the first two categories. Because of this, it is this group of people with sleep disorders that is most difficult to treat.

What reasons lead to sleep disturbance?

It should still be noted that various sleep disorders are always a manifestation of some disease. That is, this phenomenon is secondary. General classification The types of sleep disorders have many sections. We will look at the main ones, of which the most common is psychophysiological sleep disorder.
The main factor in the development of psychophysiological sleep disorders is a factor associated with a person’s mental state.

Stressful situations and psycho-emotional stress
This means that sleep disturbances occur in response to acute psycho-emotional stress or psychosocial stress. Sleep disturbance resulting from exposure to stress factors is a psychophysiological reaction. This reaction is characterized by a gradual restoration of sleep some time after the disappearance of traumatic factors.

Emotional disorders
The next factor in the development of sleep disorders is associated with emotional disorders. This is first of all anxiety disorders, mood disorders and panic disorders. Leading among emotional disorders are anxiety and depression.

Any somatic chronic diseases
There are other factors that lead to sleep disturbances, the role of which increases with age. For example, with age, pain occurs when you need to wake up at night to urinate, and the manifestations of cardiovascular and other diseases intensify. All these factors caused by the course and progression somatic diseases – various organs and systems also interfere with normal sleep.

And then the following situation arises in which people associate their poor mental state with sleep disorders. They put sleep disturbances at the forefront of their painful manifestations, believing that with normalization of sleep they will feel better. In fact, just the opposite - we need to establish normal functioning of all organs and systems, so that sleep also normalizes. To solve this problem, adjustment of the treatment regimen may be necessary. chronic diseases subject to change functional state body. Since the causes of sleep disturbance are diverse, it should be emphasized that the leading place among these causes is still occupied by psychogenic ones.

How are sleep disorders related to emotional disorders?
How do sleep disorders associated with anxiety and depression manifest? In people with increased anxiety, presomnia sleep disorders predominate. The greatest difficulty for them is falling asleep, but if they manage to fall asleep, they sleep quite satisfactorily. However, the development of intrasomnic and other manifestations is possible. People with depression are more likely to experience post-somnia sleep disorders. People suffering from depression fall asleep more or less normally, but they wake up early and then cannot fall asleep. These morning hours are the hardest for them. Depression of people with such post-somnia sleep disorders is melancholy. By evening, their condition usually improves. However, the manifestations of depression do not end there. Among patients with depression, sleep disturbances occur in 80-99%. Sleep disturbances can be, on the one hand, the leading complaint, and on the other hand, be part of a complex of other depressive manifestations.

Persistent sleep disturbances without clear causes identified this state, serve as a basis for excluding hidden, masked depression.

People with depression often report that they spend the night thinking, which still happens during sleep, although the head does not rest at all. At the same time, hypochondriacs claim that they lie awake at night and their thoughts take place while awake, that is, they are not manifestations of sleep. That is, people with depression believe that their thoughts are tormenting them while they sleep, while hypochondriacs believe that their thoughts are tormenting them while they are awake.

As we have already said, sleep disorders are more common with increasing age, when the number of depressions also increases. A connection has been found between age, depression and female gender, which is based on common neurobiochemical systemic disorders. In this case, the slow-wave sleep phase, which is the deepest sleep, decreases; eye movements become less regular. Eye movements are present during REM sleep, during which dreams occur.

An interesting aspect of sleep and depression that was noticed by chance. People who suffer from depression and go several nights without sleep feel better in the following days. This phenomenon has been studied. As a result, it was found that sleep deprivation for several weeks (sleep deprivation was carried out 2-3 times a week) helps with sad depression more than the use of antidepressants. However, when alarming form depression, such sleep deprivation is less effective. It is important to highlight that sleep deprivation increased the effectiveness of subsequent antidepressant use.

Wakefulness disturbance
However, in addition to insomnia disorders, with depression, disturbances in wakefulness are occasionally observed ( hypersomnia), states increased sleepiness. These disorders related to hypersomnia syndrome, which is manifested by deep sleep, difficulty waking up in the morning, and daytime sleepiness. This syndrome often occurs with neuroendocrine pathology. Another form of hypersomnia is narcolepsy, is a genetic disease.

And finally, another manifestation of hypersomnia is the so-called periodic hibernation. This phenomenon observed mainly in young people who experienced irresistible drowsiness for several days (7-9 days) without any apparent reason. These people got up, ate food, and relieved their physiological needs, but most spent the day sleeping. Such periods began suddenly and ended just as suddenly. These episodes were interpreted as manifestations of depression. Conducting appropriate preventive treatment in the interictal period in most cases it is effective.

Principles of treatment of sleep disorders

When clarifying the depressive nature of sleep and wakefulness disorders, it is recommended to use course treatment antidepressants. In this case, special importance is attached to drugs that have a selective effect on the serotonin systems of the brain responsible for the initiation and development of sleep.

Sleeping pills, of which there are a great many, cannot solve the problem of sleep in people with depression. They are only symptomatic remedies.

NATALIA EROFEEVSKAYA

Duration and quality of sleep– criteria that influence many factors: mood, well-being, feeling of cheerfulness. In preparation for a new day, we try to go to bed early, but in the morning we wake up exhausted and lethargic. On another day, on the contrary, after a short sleep, we wake up on our own, feeling cheerful and strong. Why does this happen and how to learn to get enough sleep? To answer these questions, we will analyze the phases of human REM and NREM sleep in time and their characteristics.

Discoveries of scientists

Today, sleep is an understandable physiological state. But it was not always so. For a long time scientists could not track what changes occur in a person during rest. The topic was closed and difficult to study. In the 19th century, they assessed a person’s posture, measured arterial pressure and temperature, and other indicators were taken. For detailed study, sleepers were awakened and changes were recorded.

Hand turns off alarm clock early in the morning

Early attempts at sleep intervention have yielded results. Scientists have found that sleep goes through stages of varying duration rapid and deep sleep of a person, and their importance is great, since it affects all indicators of the body. The German physiologist Köllschutter found that deep sleep occurs in the first hours of rest, and then it turns into superficial sleep.

After the discovery of electric waves, scientists took a complete picture of what was happening to the sleeper. An electroencephalogram helped to understand what was happening to a person during rest. In this case, the subject did not have to be woken up. Thanks to new technologies, it has become known that sleep goes through 2 phases: slow and fast sleep.

Stages of slow-wave sleep

Orthodox sleep is divided into stages. The stages differ in the duration and depth of rest. Let's look at the stages of slow-wave sleep:

First. Occurs after a person closes his eyes. The first stage is called napping. A person is not yet falling asleep; the brain is in an active stage. Within 10–15 minutes. the vacationer processes information that happened during the day. During this period, solutions are found to the questions that tormented a person.
Second. At this stage, “sleep spindles” appear. They occur at intervals of 3–5 minutes. During their passage, consciousness is completely switched off. In between sleep spindles, a person is sensitive to what is happening around him. He hears voices or sounds. This feature allows the mother to hear the baby’s cry at night. If you call a sleeping person by name, he will immediately wake up. Physiological changes boil down to a decrease in muscle activity and a slower heart rate.

During the second slow phase of sleep, a person hears sounds

Third. Stage of delta sleep or transitional. “Sleep spindles” are preserved and become longer lasting. Delta oscillations are added to them. The third stage is called preparatory stage before deep sleep.

Fourth. At this stage, the pulse quickens and blood pressure rises. The person falls into deep sleep. Dreams during this period are unclear and blurry. If the vacationer wakes up during the fourth stage, he will not remember what he dreamed.

People who sleepwalk or talk in their sleep do not remember anything the next morning. This is due to the fact that all events take place in deep stage sleep. Even if you interrupt the sleepwalker, he will not understand why he is not in bed and how he ended up in another room. It is at this stage that people have nightmares.

Duration of deep sleep directly depends on the age of the person and the physical condition of his body. For example, the duration of a child's deep sleep phase is 20 minutes, but the quality of sleep is completely different than that of most adults: it is much stronger, children may not respond to external stimuli (sound, light, touch). Thus, even the smallest ones restore energy, “reboot” the body’s systems, and charge the immune system.

How long does the deep sleep phase last? The deep sleep phase, the duration of which varies depending on the specific stage, generally lasts one and a half to two hours. Of these, 5-10 minutes are “allocated” for napping, 20 minutes for the second stage (slowing breathing and heart rate), and 30-45 minutes for the third and fourth phases.

The girl sleeps sweetly, hugging a pillow

Features of REM sleep

After deep sleep ends, REM sleep begins. The fifth stage was discovered by Kleitman in 1955. The recorded indicators made it clear that the indicators of the body during REM sleep in humans are similar to the state of wakefulness. The REM sleep phase is accompanied by:

constant movement of the eyeballs;
significant decrease in muscle tone;
emotionally charged and action-packed dreams;
complete immobility of a person.

How long does REM sleep last? In total, shallow sleep makes up 20-25% of the average night's rest time, i.e. one and a half to two hours. One such phase lasts only 10-20 minutes. The most vivid and memorable dreams come during the REM sleep stage. If a person is awakened during this period, he will fully tell what he dreamed.

Baby is sleeping

Why are sleep phases needed?

A person’s well-being is inextricably linked with rest and sleep. No wonder. In the first months of life, a little person has a strong connection with nature and obeys its laws. As adults, we make decisions about how much sleep we need. Often untrue, so the mental is disturbed, emotional condition person - that is why it is important to know the frequency of fast and deep stages in night sleep and be able to calculate the stages of sleep for the time of awakening.

Scientists calculated sleep phases and after a series of studies came to the conclusion that 4–5 cycles pass per night. During this period, the person is restored. During slow-wave sleep, energy expended during the day is replenished. REM sleep is short in the first cycles, then lengthens. During the fifth phase, a person processes information and builds psychological protection, adapts to the environment. Knowing how to calculate the sleep cycle, it is possible to learn how to regulate the body’s energy capacity and its vital functions as a whole.

Studies done on rats have shown that Lack of REM sleep leads to death. The rodents were deliberately awakened, preventing the rats from entering the fifth stage. Over time, the animals lost the ability to fall asleep, after which they died. If the sleeping person is deprived fast phase, then the person will become emotionally unstable, prone to irritation, mood swings, and tearfulness.

Girl sleeping with hand on alarm clock

How to calculate sleep phases to know when is the best time to wake up?

Let's take as a basis that one cycle lasts for 90 minutes. Long REM sleep is required for proper rest. Therefore, at least 4 cycles should pass overnight. Waking up during slow-wave sleep makes a person groggy and lethargic. So, we need to calculate how to wake up during REM sleep: The fifth phase is characterized by active brain function, so awakening occurs gently and painlessly.

Let's summarize. To feel cheerful in the morning, the duration of sleep and awakening after the completion of the fifth phase are important. For an adult, the ideal sleep time is 7.5–8 hours. The best option- This self-awakening, no alarm or phone signal.

If during the day you feel weak and want to take a nap, then allow this luxury. To avoid harm, record your rest time. If you have slept enough time at night, close your eyes for 15–20 minutes. This is how long the first stage of slow-wave sleep lasts. You will not have time to fall asleep, but you will feel that fatigue has been relieved. If night sleep was short-lived, then go through one cycle during the day. Sleep for 1–1.5 hours.

Conclusion

The data given is approximate, but the essence is clear. For normal life human body phase sleep is necessary. It is important to wake up after completing 4–5 cycles. It’s ideal when you wake up on your own. Daytime nap It won’t do any harm if you prevent the second phase from entering or if you go through one full cycle.

January 20, 2014, 11:36

Rest refers to a necessary phenomenon through which processes are carried out: replenishment of energy and physiological costs. Scientists distinguish 2 phases of sleep - slow and fast.

Due to individual characteristics and excessive workload at work, it has become necessary to calculate an acceptable time to wake up in the morning. With correct calculations with the sunrise, a person will have a paradoxical result: high spirits, improved performance in any area. In addition, they will not develop concomitant diseases, such as insomnia.

The value and functions of sleep

An acceptable and recommended sleep period for adults is considered to be up to 12 am. Only at this moment is the human body able to restore the energy and physiological activity required for full performance.

The table shows valuable hours for a specific time period.

Times of Day	The value of sleep per hour
19-20 hours	7 o'clock
20-21 hours	6 hours
21-22 hours	5 o'clock
22-23 hours	4 hours
23-24 hours	3 hours
0-1 hour	2 hours
1-2 hours	1 hour
2-3 hours	30 minutes
3-4 hours	15 minutes
4-5 hours	7 minutes
5-6 hours	1 minute

Based on the above data, you can clearly see how important it is to go to bed on time. This affects the performance of the whole organism, and therefore shapes the further mood and well-being of a person.

Several main functions have been identified through which it becomes possible to form an idea of ​​​​the benefits:

1. Internal organs and muscle tissue remain in a relaxed state at night, gaining strength.
2. During the day, a person expends a lot of energy for full-fledged activities, but only during sleep are the reserves replenished.
3. A lot happens when you're on vacation necessary processes dictated by the brain. This is the removal of waste and toxins, rebooting the central nervous system, cleansing the brain center.
4. Also, during sleep, long-term memory is formed, which includes accumulated information. This includes understanding what you see and consolidating new skills.
5. The main component is the analysis of the state of internal organs; if violations are identified, they should be eliminated. As a result, immunity improves, because new cells are formed during sleep.

Sleep is a necessary component in the life of every person. Without it it is impossible to live to the fullest. A necessary requirement is that you need to fall asleep at the recommended interval, because this can increase efficiency and prevent the development of certain diseases.

Cycle duration

Sleep is a state of consciousness of all living things, which includes 5 stages. They replace each other during the night's rest. The occurrence is explained by the activation of brain centers.

In an adult who does not have serious problems With health, falling asleep begins with a nap. It doesn't take much time - only 10 minutes. After this, stage 2 enters. Lasts a little longer - 20 minutes. The remaining two stages take at least 45-50 minutes.

As soon as initial process, consisting of 4 stages, passes, and the action of stage 2 occurs again. At this moment, the first episode of REM sleep appears. But it doesn’t last long – 5 minutes. Such sequential processes are formed into cycles. The first one takes 1.5 hours or a little longer. Afterwards, the cyclicity resumes, but slow-wave sleep disappears. This is because REM sleep comes into play. Sometimes it takes 60 minutes.

Important! With proper rest, approximately 5 cycles. The sequence and duration vary slightly, depending on the individual characteristics of the body.

Most studies confirm that fast and slow phase are characterized of different durations in a ratio of 1:4. In this case, the first spends 85% of the rest time, but the second accounts for 15%. One cycle lasts 1.5 hours. It is important for a person to sleep 6-8 hours. Based on this, the cycles can be repeated 6 times. But the meanings are variable, depending on the specific case.

In young children, the process takes place in a slightly different sequence. REM sleep predominates, which is gradually replaced. Initially, it accounts for 50%, and as the baby develops, this figure decreases to 25%.

In an adult, the stages should tend to repeat in equal sequence. However, due to age characteristics And serious pathologies It is possible to observe some disturbances in normal sleep. Elderly people often face problems of insomnia, because the fast phase makes up no more than 18%, and the slow phase is completely absent.

However, there are other reasons quality rest: diseases of the brain or spinal cord. In this case, it is impossible to sleep normally; there is superficial sleep. It is rare, but it is observed that a person does without rest at all, even short.

Slow phase

Certain brain centers are involved in the formation of slow-wave sleep: the hypothalamus, thalamic nuclei, and the inhibitory department of the moruzzi.

Important! Main feature slow sleep is the formation of new cells and structures, tissue restoration. This process must occur at rest with the participation of certain hormones, amino acids and proteins.

The end result of anabolic processes is considered to be the replenishment of energy that is lost during performance during the day. Their activity begins from stage 2, because at this moment complete relaxation occurs. Therefore, such a period is considered favorable for restoring lost energy and physiological reserves.

Important! It has been proven that moderate physical exercise per day contribute to the prolongation of stage 4 of the slow phase.

When falling asleep, certain rhythms appear, which depend on the good illumination of the room by sunlight. The onset of dusk signals a decrease in some activity. At this moment, the first sleep triggers are observed: yawning and weakness.

Each stage has a specific time interval. So, 8% is spent on the third, and 15% of the entire period spent on sleep is spent on the fourth. Many attribute the slow phase to the restoration of energy resources. Only it is fundamental in understanding actions and memories.

The main signs of this stage of sleep are considered to be loud breathing, which gradually becomes rarer and less deep than during wakefulness. There is a decrease general temperature, activities muscular system and eye movements. During the slow phase of sleep, a person can see minor dreams; on the encephalogram, slow and long waves begin to predominate.

The first stage is drowsiness

It refers to stage 1 of falling asleep. In this state, the sleeper is able to see phenomena and actions that bother him while awake. In addition, this has a clear characteristic:

• heartbeat weakens;
• breathing slows down;
• the temperature drops;
• you can catch the slow movements of the eyeball.

Also, an altered state is recorded in a brain hologram, accompanied by surges in mental activity. At the same time, it is recorded that a solution comes difficult situation, which was difficult to resolve in the process of life. Main fact: awakening a person from stage 1 slow-wave sleep is not difficult.

Stage two - light sleep

During shallow sleep, the consciousness of reality gradually begins to turn off, but it is still possible to react to voices or sounds. At the same time, certain processes occur in a sleeping person: a decrease in temperature, any activity weakens, and pressure drops. With repeated studies, the sequence of stages of the slow phase is comparative (with the spindle), because over time all actions decay. Ultimately - immersion in a deep state.

Stage three - slow-wave sleep

A somewhat different state develops at this stage, since all movements come to naught. This can be verified through brain research. At the same time, the pulsation is weak, sighs become more frequent, the pressure level drops, and the pupils practically do not move. Blood flow to muscles and tissues is also manifested, and growth hormone is formed. All this characterizes the process that has begun in the body to replenish energy.

Stage four - deep sleep

The last stage is responsible for complete immersion in sleep. The phase is accompanied by a blackout of consciousness; it is impossible to even feel, feel or hear anything. That is why there are no special unexpected manifestations from the body: breathing is difficult to observe, extraneous movements of the eyeballs or body parts are not observed.

In the state of the deep phase, it is almost impossible to raise a sleeping person to his feet. If this is done, poor orientation in space, slower reactions, bad feeling, it is not possible to catch the ghostly thing. Sometimes people wake up in a good mood and experience nightmares. But this stage is not felt upon awakening.

Basically, stages 3 and 4 are classified as one, in which case their duration is about 40 minutes. High-quality and timely rest creates activity for work for the coming day. If the deep sleep stage is complete, it is possible to remember some information after waking up.

Fast phase

When rest is reorganized into a fast phase, unusable knowledge and skills are cleared in the emotional and intellectual areas. At this time, active activities take place:

• To restore nerve cells. There is an opinion that this is impossible, but these are unreliable assumptions.
• By understanding the information received during the day.
• At the start of preparations for mental activity.

Due to the existence of a single stage of the fast phase, its duration increases, which is 15%. Its main goal is to process the received information with the possibility of its further application. In addition, this phase is mandatory, because it is required for the complete restoration of the nervous system.

Significant changes were revealed during REM and slow-wave sleep. This manifests itself in characteristic actions and movements, some of which can be observed visually:

• Difficulty breathing when exhaling deeply.
• Deviations from the normal heartbeat.
• Muscle tone weakens, which can be more clearly observed in the neck of the mouth.
• The pupils perform unconscious movements at an accelerated pace.

In this phase, dreams are the most emotional. They may be dominated by bright and significant moments from life or various situations transferred the previous day.

If a sleeper is awakened in the REM phase, he will clearly and clearly reproduce the dream. Awakening in this phase is easy because no discomfort is felt. On the contrary, your mood lifts and your well-being improves.

Through alternating phases, some changes are revealed with their effect on the body. The next morning, the likelihood of waking up in the fast phase increases, but the slow phase decreases. If it is impossible to go to bed at the conventional time, the fast phases will be shortened, but the slow phases will not be in danger.

Features of awakening in each phase of sleep

Sleeping is characterized by heterogeneity, and several phases have been identified that particularly affect the body. Each of them has specific phenomena brain system. The main task is to replenish energy and physiological resources.

If we talk about the correctness of phase awakenings, then you need to have information about each one. First, it is worth highlighting at what stage the interruption occurred. Problems will arise in the slow phase, because the most significant processes are being restored.

Awakening in the fast phase is facilitated, regardless of the colorful and vivid moments that can be seen in dreams. But the absence of this phase for a long time can negatively affect a person’s well-being, undermining psychological background. She is the link between consciousness and subconscious.

How to calculate the optimal time to wake up

All stages of sleep play an important role for humans. This will allow the body to restore strength and energy. The best solution is to adhere to the regime without breaking it. It is good if the cycles are completed by 4:00, since slow-wave sleep gradually declines after midnight. It is not necessary to do this, perhaps sleep more. It allows the nerves to recover at this very time when the fast phase begins.

To ensure quality rest that has beneficial effects, it is important to go to bed early. This will help maintain the duration of the phases.

Most people are curious if there is a special technique that would make it possible to calculate the best time to wake up on their own. So that at the same time you feel a surge of strength, with a further desire for mental and physical labor. Dymaxion is a common technique that involves sleeping for 30 minutes 4 times a day.

Using the slow and fast phases of sleep, how to get enough sleep? If awakening occurs in the slow phase, then fatigue is guaranteed. Therefore, it is better to do it in a quick phase. Careful calculations will allow you to track the correct time. This is easy to do; you just need to build a graph. But you are also allowed to use a calculator.

Based on somnological studies, it is known that sleep cycles take 2 hours, with fast sleep only 20 minutes. Using this data, it becomes possible to calculate an acceptable time to wake up.

However, full recovery requires 6-8 hours. After making the calculations, you should set the resulting value on the alarm clock face.

To figure out positive influence when waking up in the fast phase, you can only do it yourself, for this you need to try it. But this does not mean that you will be able to fall asleep right away. Therefore, when making calculations, it is important to leave a little time in reserve.

Human sleep phases by time table

In a dream, a person arrives at one stage: fast or slow. The special features of each of them can be found in the table below:

slow sleep	REM sleep
Napping is the first stage. It is characterized by vivid thoughts and memories that arise on a subconscious level. At this moment, the sleeper is in a superficial sleep, which lasts 5-10 minutes.	Quick is separate and last stage. At this moment the person is in a state of activity. However, his movements are constrained, because motor function absent due to paralysis. The subconscious mind works harmoniously, so you can remember a lot useful information received per day. Awakening is not easy. This may have a negative impact on mental state. The fast phase takes 60 minutes.
When it is shallow, characteristic manifestations are possible: consciousness is switched off, but the auditory reference point (external voices, sounds) is heightened. For this very reason, sudden awakenings often occur. The duration of the stage is only 20 minutes.
The third stage is characterized by obvious immersion in sleep.
The fourth stage involves deep sleep. It is difficult to wake up a sleeping person. At the same time, dreams are clearly expressed. A person may have a disease - sleepwalking. The next morning it is difficult to remember what you dreamed; only some moments are remembered. More often, stages 3 and 4 are combined into one, each lasting about 45 minutes.

The table describes the phases of human sleep by time and characterizes the stages occurring in a specific phase. With the completion of all stages, the end of the first cycle comes. Sleep should be cyclical, so for quality rest the body must go through 5 cycles. The stages replace each other gradually. Doctors recommend getting at least 8 hours of sleep. If you constantly violate the recommendations, you can develop a disease - a mental disorder.

Sleep takes place in 2 phases: slow and fast. In young children, the fast phase predominates, which differs from adults. At the moment of sleep, it is possible to see the movements of the eyeball, while the baby has colorful dreams. Muscle tone weakens, but this does not affect the nasopharynx and eyes. Movements are limited.

It is known that during the growth and development of a child, the need for sleep is paramount. But everyone decides for themselves how much sleep they need. This is dictated by the body, namely individual characteristics: physiological, mental.

The norm for a child is determined depending on age guidelines:

• 1-2 months - 18 hours;
• 3-4 months - 17-18 hours;
• 5-6 months - 16 hours;
• 7-9 months - 15 hours;
• 10-12 months - 13 hours;
• 1-2 years - 13 hours;
• 2-3 years - 12 hours;
• 3-5 years - 10-13 hours;
• 6-13 years – 9-11 hours;
• teenagers 8-10 hours.

Over time, children spend fewer hours resting in order to get a good night's sleep. This is dictated by changing needs and increased load on the brain. The most active ones need little time at all to gain strength for a productive day.

2013-03-05 | Updated: 2018-05-29© Stylebody

Scientists have long proven that good sleep, which includes two main phases - slow and fast - is extremely important for human health and well-being. And this fact must be taken into account when creating a daily routine. There is an old folk saying that states that “the morning is wiser than the evening.” And indeed, to accept important and complex solutions It's much easier in the morning than at night. In addition, each of us has noticed how lack of sleep affects well-being and performance. A sleepless night may entail not only a sharp decline mental activity, but also headache, weakness, weakness and other unpleasant symptoms.

Physiology of sleep

The human body is designed in such a way that all processes occurring in it are tied to a certain daily time and largely depend on the change of day and night. Sleep and wakefulness constantly alternate between each other and occur at approximately the same time. And if normal rhythm sleep-wakefulness is suddenly disrupted, this has the most negative impact on the work of various human systems and organs. From chronic lack of sleep First of all, the nervous and immune system, which can lead to the gradual disabling of the entire organism.

Wakefulness and sleep are two opposite and, at the same time, interconnected states. When a person is awake, he actively interacts with environment: eats, exchanges information, and so on. During sleep, on the contrary, there is an almost complete disconnection from the outside world, although important processes in the body itself do not stop. It is estimated that sleep and wakefulness are in a 1:3 ratio, and any deviation from this norm is dangerous to health.

Scientists have been able to record changes that occur in the human brain during sleep using a research method such as electroencephalography. It allows you to make a graphic recording in the form of waves, the decoding of which provides information about the quality of sleep and the duration of its different phases. This method is mainly used for diagnosis various violations sleep and to determine their degree negative influence on the body.

When the mechanism that regulates the frequency of sleep and wakefulness is disrupted, various pathological conditions arise, such as narcolepsy (an irresistible desire to fall asleep that occurs during the day), as well as hypersomnia (an exaggerated need for sleep when a person sleeps much more than normal).

Sleep is characterized by a quality called cyclicity. Moreover, each cycle lasts an hour and a half on average and consists of two phases - slow and fast. For a person to get enough sleep, four to five such cycles must pass. It turns out that you need to sleep at least eight hours a day.

The main differences between the phases are:

Duration The predominant phase is the slow phase. It takes up approximately 80% of the time of the entire sleep process and, in turn, is divided into four stages. The fast phase takes significantly less time, and its duration increases in the morning, closer to awakening. Purpose The purpose of sleep phases is different. During the slow phase they are restored internal organs, the body grows and develops. The fast phase is needed to activate and regulate the nervous system, to organize and process accumulated information. During REM sleep, children develop the most important mental functions - which is why in childhood we so often see vivid, memorable dreams.

Brain activity The differences between the slow and fast phases in terms of brain activity. If during slow-wave sleep all processes in the brain slow down significantly, then in the REM sleep phase they, on the contrary, are extremely activated. That is, a person is sleeping, and his brain is actively working at this time - that’s why REM sleep is also called paradoxical. Dreams People see dreams throughout the entire cycle, but those dreams that occur during the fast phase are better remembered. The dynamics of dreams also strongly depend on the phase - the slow phase is characterized by restrained dreams, during the fast phase they are more vivid and emotional. Therefore, it is morning dreams that most often remain in memory after waking up.

How does the sleep process proceed?

When a person becomes drowsy and falls asleep, the first stage of non-REM sleep begins, lasting a maximum of ten minutes. Then, as the second, third and fourth stages occur, sleep becomes deeper - all this lasts approximately 1 hour 20 minutes. It is the fourth stage of the first phase that is characterized by such well-known phenomena as sleepwalking, talking in sleep, nightmares, and childhood enuresis.

Then, for a few minutes, there is a return to the third and second stages of slow-wave sleep, after which the fast phase begins, the duration of which in the first cycle does not exceed five minutes. At this point, the first cycle ends and the second cycle begins, in which all phases and stages are repeated in the same sequence. In total, four or five such cycles change per night, and each time the REM sleep phase becomes longer and longer.

In the last cycle, the slow phase may be exceptionally short, while the fast phase is predominant. And it’s not for nothing that nature intended it this way. The fact is that waking up during REM sleep is very easy. But if a person is woken up when slow-wave sleep is in full swing, he will feel exhausted and sleep-deprived for a long time - one can say about him that he “got off on the wrong foot.”

NREM sleep phase (4 stages)

Stage	Description	Duration
Nap	The pulse and breathing slow down, the eyes move slowly under closed eyelids. Consciousness begins to float away, but the mind still continues to work, so at this stage people often come to interesting ideas and solutions. In a state of drowsiness, a person wakes up relatively easily.	No more than 5-10 minutes.
Sleepy spindles	The name of the second stage of slow-wave sleep is associated with the encephalogram graph. During this period, the human body relaxes, but the brain still remains sensitive to everything that happens around it and reacts to the words and sounds heard.	Approximately 20 minutes.
Delta sleep	This stage precedes deep sleep. Characterized by a slight increase in heart rate, breathing is also rapid, but shallow. Blood pressure drops, eye movements become even slower. At the same time, active production of growth hormone is observed, blood flows to the muscles - thus the body restores energy costs.	About 15 minutes.
Deep dream	At this stage, consciousness is almost completely turned off, the eyes stop moving, breathing becomes slow and shallow. A person sees dreams of neutral, calm content, which are almost never remembered. Waking up during deep sleep can only be forced and occurs with great difficulty. A person awakened at this stage feels overwhelmed and lethargic.	From 30 to 40 minutes.

REM sleep phase

When a person enters the REM phase of sleep, it can be seen even from the outside. He starts to move actively eyeballs, breathing either quickens or slows down, facial movements may be noticeable. The devices record a slight increase in body and brain temperature, increased cardiovascular activity. During this phase, the process of exchanging information accumulated during wakefulness between consciousness and subconscious occurs, and the energy that the body managed to accumulate during slow sleep is distributed. A person sees colorful dreams that he can remember and retell after he wakes up. Waking up during REM sleep is the easiest and fastest.

How much sleep do you need to get enough sleep?

According to scientists, a person needs to sleep from 8 to 10 hours a day, which equals 4-6 sleep cycles. It should be taken into account that the duration of the sleep cycle is different people is not the same and, depending on the individual characteristics of the nervous system, can vary from 1.5 to 2 hours. And so that the body receives good rest, there should be at least 4-5 such complete cycles. How much sleep a person should have is largely determined by his age.

Here are the approximate sleep norms for different age groups:

• Most long sleep for unborn babies in the mother's womb - about 17 hours a day.
• Newborn babies spend 14 to 16 hours sleeping.
• Babies aged 3 to 11 months need to sleep 12-15 hours.
• One- and two-year-old children sleep 11-14 hours a day.
• It is advisable for preschoolers to sleep at least 10-13 hours.
• The body of primary school children under 13 years of age requires 10 hours of rest at night.
• Teenagers are recommended to sleep between 8 and 10 hours.
• Sleep duration of an adult from 18 to 65 years, depending on personal characteristics body, is 7-9 hours.
• The need of people after 65 years decreases slightly - they need to sleep from 7 to 8 hours.

How to sleep less and get enough sleep

The quality of sleep is very dependent on what time a person goes to bed. Sleeping until midnight from 19.00 to 24.00 is extremely beneficial. People who are accustomed to falling asleep early feel refreshed and well-rested, even if they get up at dawn. In this case, a person can sleep less, but still get enough sleep. And the trick is that the value of sleep in a certain period of time is different.

Sleep value table by hour

Sleep period	The value of rest
19.00 — 20.00	7 hours
20.00 — 21.00	6 hours
21.00 — 22.00	5 hours
22.00 — 23.00	4 hours
23.00 — 24.00	3 hours
24.00 — 01.00	2 hours
01.00 — 02.00	1 hour
02.00 — 03.00	30 min
03.00 — 04.00	15 minutes
04.00 — 05.00	7 min
05.00 — 06.00	1 min

What time is best to get up in the morning?

It is believed that the best time to wake up is from 4 to 6 am. People who rise with the sun are not afraid of fatigue, and they manage to do a lot in a day. But, of course, in order to get up early, you need to develop the habit of going to bed early. In addition, people have different biological rhythms. As you know, people are divided into “night owls” and “larks”. And if a person is a night owl, then it is better for him to wake up around 8-9 in the morning.

How to correctly calculate your wake-up time

It is very difficult to independently calculate the time for which you need to set an alarm clock in order to wake up in the REM sleep phase. As mentioned above, each person's sleep phases have an individual duration. Therefore, before carrying out such calculations, you must first contact medical Center so that specialists can determine your personal sleep rhythm using special instruments.

Although it is possible to calculate the approximate time When is the best time to wake up? To do this you need to take average duration slow sleep phase (120 minutes), as well as the average duration of fast sleep (20 minutes). Then you should count 5 such periods from the moment you go to bed - this is the time you set the alarm clock. For example, if you fell asleep at 23:00, then best time Your wake-up time will be from 7:20 to 7:40 am. If you decide to sleep longer, for example on Sunday, then the time to get up correctly will be between 09:00 and 09:20.

The importance of sleep for the body

• The main purpose of sleep is to allow the body to rest and recover. Prolonged insomnia is fraught with serious health problems. Experiments on animals have shown that a complete lack of sleep after a certain time causes hemorrhages in the brain. People who are chronically sleep deprived soon experience increased fatigue, and then problems with the cardiovascular system join.
• Sleep affects metabolic processes in the body. While a person is in slow-wave sleep, growth hormone is produced, without which protein synthesis cannot occur - therefore, lack of sleep is especially dangerous for children. In people who lack sleep, the cleansing and restoration processes in the body are also disrupted, since during sleep, organ cells are actively supplied with oxygen, and the work of the liver and kidneys, which are responsible for neutralizing and removing harmful substances, is activated.
• During the fast phase, the distribution, processing and assimilation of accumulated information occurs. By the way, as it turned out, it is impossible to learn and remember anything during sleep (the method of teaching foreign languages ​​to sleeping people has not justified itself), but the information that entered the brain immediately before sleep is indeed better remembered.
• REM sleep promotes the activation of all neurohumoral processes - the human nervous system is tuned to active work. It has been noticed that a lot of nervous diseases appear from lack of sleep.

The effect of sleep on the cardiovascular system

Many of us are accustomed to regularly invigorate ourselves with tonic drinks - strong tea, coffee. Yes, this way you can really cheer yourself up for a short period of time. But then, when caffeine stops working, the person feels even more tired, drowsiness and weakness appear. Therefore, there is nothing better for cheerfulness than normal sleep. People who systematically cut down their sleep time, thereby force their body to work under overload and lead it to exhaustion, as a result of which such problems arise. serious illnesses like ischemia, chronic, and so on.

The effect of sleep on appearance

Medical scientists unanimously claim that lack of sleep provokes oxygen deficiency in the body and inevitably leads to early aging and significant deterioration. appearance. A well-rested person, as a rule, can boast not only of vigor, but also a fresh appearance, good color faces. By the way, metabolic disorders, which can lead to chronic insomnia, often entail increased appetite and... Therefore, athletes and actors, for whom it is vital to always be in good physical fitness, strictly adhere to the sleep-wake schedule.

Sleep and human behavior

It has been noticed that in people who do not get enough sleep, such negative character traits as capriciousness, short temper, irritability, and aggressiveness become more acute. And all because their nervous system is not ready for stress and is constantly on edge. But among those who get good sleep, it prevails great mood and full psychological readiness to overcome life's problems. Therefore, if your work involves night shifts, be sure to compensate for the lack of sleep during the day. Drivers should never get enough sleep. Great amount accidents occurred due to the fact that a sleep-deprived driver was distracted or fell asleep at the wheel.

And finally, we should remember one more function of sleep - through dreams, our subconscious often sends us hints and insights that help us solve important life problems.

Despite the fact that the site already has an article about sleep phases, it seems correct spelling one more article in light of what has appeared new information about sleep cycles and the amount of time it takes a person to get enough sleep.

In order not to duplicate information, I refer everyone to the article Phases of Human Sleep. And in this article we will only do short review the most necessary points regarding sleep phases.

Another thing is sleep cycles. It is the required number of sleep cycles that gives us the opportunity to feel great in the morning after waking up. Moreover, each individual person may differ markedly from others in the number of necessary sleep cycles and, as a result, the time spent on night sleep.

In addition, I think it will be interesting to learn about what capabilities the human body has to compensate for the lack of sleep, both for the previous lack of sleep and for the future.

Let's look at all this in order.

Sleep phases

The sleep phases of any person consist of only two groups:

1. Non-REM sleep phase (consists of several types of sleep);
2. REM sleep phase.

These two sleep phases constantly alternate throughout a person’s entire sleep time, forming a single completed sleep cycle. That is, the sleep cycle consists of 1 phase of slow sleep and 1 phase of REM sleep. The duration of the sleep cycle usually ranges from 1 to 1.5 hours. Then a new cycle of similar duration begins.

Non-REM sleep stages initially occupy up to three-quarters of the total duration of the sleep cycle. But with each new cycle, the duration of the sleep phase within a given cycle changes towards reducing the duration of slow-wave sleep and increasing the rapid phase.

According to available data, somewhere after 4 o'clock in the morning, the phase of slow sleep (deep type) completely disappears, leaving only REM sleep.

What happens during non-REM and REM sleep?

The human body needs slow-wave sleep for recovery physical functions. At this time, the process of renewal of cells and internal structures occurs, energy is restored, muscles grow, and hormones are released.

During the REM phase of sleep, work occurs at the level of mental and emotional spheres: the nervous system is restored, information is processed, memory and other structures of the body are prepared.

It turns out that each phase of sleep is extremely important for the next day of the body’s functioning.

Sleep cycles

But during one phase of sleep, the body does not have time to make all the necessary changes. Therefore, in order to fully restore and prepare the body for further activities Several repeating cycles are needed throughout the day.

Today, scientists say that the average person needs 5 repeating sleep cycles. This adds up to about 7-8 hours of sleep a night.

However, there are a fair number of people who have deviations in the number of cycles in one direction or another.

There are people who are able to fully recover in just 4 sleep cycles. They often only need 4-6 hours of sleep during the night to feel great the whole next day.

On the other hand, many people feel constantly groggy if they sleep less than 9 hours a night. Compared to other people who sleep fewer hours, such people look lazy. However, if you understand that they just need not 5, but 6 sleep cycles at night, then everything falls into place. 6 sleep cycles of 1.5 hours each give you 9 hours of sleep at night.

How much sleep do you need to get enough sleep?

To get enough sleep, each individual person needs to sleep exactly as many sleep cycles as his body requires. Usually this is 4-6 sleep cycles.

At the same time, the duration of sleep will also fluctuate considerably, because... Each person has their own sleep cycle length.

Scientists recognize 4 sleep cycles as the minimum that allows the body to more or less restore its strength. But at the same time, it is necessary to ensure that all these 4 sleep cycles are completed before 4 o’clock in the morning. This will completely complete all the body’s work to restore physical structures.

In any case, every person knows approximately how many hours of sleep he needs to feel normal. Based on this, we can conclude about the required number of sleep cycles.