The Importance of Good Sleep for Health

Sleep is a spontaneous and reversible resting state that occurs periodically in higher vertebrates, which is manifested by a decrease in the body's responsiveness to external stimuli and a temporary interruption of consciousness. About 1/3 of a person's life is spent in sleep. When people are in a state of sleep, it can make people's brain and body rest, rest and recovery, and the right amount of sleep is helpful for people's daily work and study. Scientific improvement of sleep quality is the guarantee of people's normal work, study and life.

Basic information

Chinese name: sleep, sleep Chinese sleep, sleep name: sleep, sleep

Name: sleep

Reason: Organize memory

Category: Biological Behavior

Reasons for Sleep

Sleep is due to the internal needs of the body, so that sensory activities and motor activities temporarily stop, give appropriate stimulation can make it immediately awake state. People recognize the brain electrical activity, that sleep is due to the functional activity of the brain caused by the animal physiological activity is low, give appropriate stimulation can make it fully awake state.

Sleep is an active process. Sleep is the rest necessary to restore energy. There is a special central management of sleep and awakening. When sleeping, the human brain only changes a working mode to store energy, which is conducive to the recovery of mental and physical strength. Proper sleep is the best rest, which is not only the basis for maintaining health and physical strength, but also the guarantee for achieving high productivity. Nerve cells with higher excitability that receive and respond to internal and external stimuli prevent the interaction of stimuli that have not been further processed from interfering with each other, which is manifested as fatigue relief. And sleep quality is not high refers to the shielding degree is not enough or sleep time is not enough to fully digest the phenomenon of stimulation connection. Sleepiness is morbid too much too long shielding. These are manifestations of inadequate neural control. During sleep, the state of the body is also restored due to the weakening of active activities.

The most important function of sleep is reflected in the brain, and the sleep state connects the scattered memory fragments in the brain through dreaming. Get up and put together.

physiological changes

Sleep is often a state of unconscious pleasure that usually occurs in bed and at night when we allow ourselves to rest. Compared with the awakening state, the contact between people and their surroundings stops during sleep, the conscious consciousness disappears, and they can no longer control what they say or do. In the sleeping state, the muscles relax, the nerve reflexes weaken, the body temperature drops, the heartbeat slows down, the blood pressure drops slightly, the metabolism slows down, and the peristalsis of the gastrointestinal tract is also significantly weakened. At this time, it seems that the sleeping person is still and passive, but in fact, if a person is given an EEG when he is sleeping, we will find that the electrical pulses issued by brain cells during sleep are not weaker than when he is awake. This proves that the brain is not resting. Just like a hive at night, the bees appear to have returned to rest, but in fact all the bees are busy all night to make honey.

After normal adults fall asleep, they first enter the slow wave phase, usually 1~2~3~4~3~2 and so on, lasting 70~120 minutes, I .e. they turn to heterophasic sleep, about 5~15 minutes, thus ending the first phase transition, then starting the slow wave phase, and turning to the next heterophasic sleep, thus going on over and over again. During the whole sleep process, there are generally 4 to 6 transitions, the slow wave phase time course is shortened successively, and the second phase is the main phase, while the out-of-phase time course is gradually prolonged. With 100 per cent full-time sleep, slow-wave sleep accounts for about 80 per cent and heterophasic sleep for 20 per cent. The different phases of sleep and wakefulness are arranged according to the time sequence of their appearance, which can be drawn into a sleep map, which can intuitively reflect the dynamic changes of each phase of sleep.

sleep mode

Sleep is composed of two alternating phases, one is slow wave phase, also known as non-rapid eye movement sleep, and the other is heterophasic sleep, also known as rapid eye movement sleep, in which rapid eye movement occurs and often dreams. REM sleep is mainly used to restore physical strength, non-REM is mainly used to restore mental power.

slow wave sleep

According to the characteristics of human brain waves, this phase is usually divided into 4 different phases, which corresponds to the process of sleep from shallow to deep. Phase 1 presents low-voltage brainwaves, with a mixture of fast and slow frequencies, and a frequency of 4 to 7 weeks/second, which often occurs at the beginning of sleep and brief awakening at night.

Non-rapid eye movement sleep is more common in the first half of the night, mainly because ordinary people have a great brain power after a day of brain use. For brain cells and brain tissues, both pressure and injury, the physiological clock will naturally induce sleep, let the brain temperature drop, and enter the repair stage, which is very important for the maintenance of life. In the second half of the night, there will be more REM sleep, which is related to study and work. When you experience a lot of good or bad scenery in a day, it should be included in your memory. Non-REM sleep includes learning new things and integrating daytime emotions.

paradoxical sleep

Heterophasic sleep refers to the regular left and right swings of the two eyeballs under the eyelids when sleeping. Staggered regularly throughout the night, sleep is medically called a sleep cycle. There will be 4 to 5 sleep cycles in a night. Non-REM sleep is maintained more in the first half of the night and almost none in the second half of the night. However, rapid eye movement sleep is increasing in the second half of the night.

It is a state of agitation that occurs periodically during sleep. The EEG shows fast-frequency low-voltage waves, similar to brain waves during wakefulness. The activity of the autonomic nervous system is enhanced, such as heart rate, respiration, blood pressure, cerebral blood flow and oxygen consumption are increased, and in men there is penile erection. In addition, the sleeper turns over from time to time, and the muscles of the face and fingers (toes) twitch from time to time. In experimental animals, it was also recorded that the discharge activity of individual nerve cells was not only higher than the slow wave phase, but also sometimes exceeded the level of activity in the awake state. Human heterophasic sleep, like animals, shows three characteristics: ① low voltage, fast frequency brain waves; ② relaxation of neck muscle tension and inhibition of spinal cord reflex, at which time the motor system is strongly inhibited; ③ frequent rapid eye movements, while in some brain structures related to vision, including the cerebral cortex, there are tall sharp waves, collectively, pontine-geniculate-occipital cortical wave (PGO). Since REM only occurs in paradoxical sleep, the latter is often called REM sleep.

deep sleep

It is generally measured by reduced physical activity and reduced sensory sensitivity. In addition, some physiological indicators, especially the arousal threshold, also indicate that the third and fourth periods of the slow wave phase are deep sleep periods. As for the depth of heterophasic sleep, it is difficult to determine, because it shows relaxation of muscle tension, and often shows whole body turnover and facial and finger muscle twitching. In terms of feeling, it is difficult for the sleeper to be awakened by irrelevant external stimuli. However, when the stimuli have special meanings or are related to the contents of his dreams, he will think it is what happened in the dream for the first time. If the stimuli are stimulated more than many times, it is easy to wake up. These contradictions suggest that an active process occurs in the brain during paradoxical sleep that cuts it off from extraneous stimuli. If judged according to the activity of the autonomic nervous system, the heterophasic sleep is closer to the awakening state. If the sleeper is awakened in this phase, he will say that he is sleeping soundly. On the contrary, if you wake him up in the slow wave phase, you will say that you are not sleeping soundly. It is speculated that this subjective sleep awareness may be related to his dreams. In summary, accurate measurement of sleep depth is difficult, and the tendency is to treat the hetero-phase and slow-wave phase as two independent states.

Some autonomic nervous activity changes with the development of sleep process, which seems to have little relationship with the two phases. For example, body temperature gradually drops from the beginning of sleep, reaches its lowest point at 5 to 6 hours, and then gradually rises again. It has been suggested that oral material can still be learned during sleep, but EEG analysis proves that the sleeper is actually in a hazy state. Sleeptalking mostly occurs in the second phase of slow wave sleep, while sleepwalking occurs in the fourth phase of slow wave without exception, and both are generally independent of the content of the dream.

Sleep time

The average newborn sleeps 16 hours a day, and the baby's sleep time is gradually shortened to about 9 to 12 hours at the age of 2. The sleep time of adults varies from person to person, usually ranging from 6 to 9 hours, and 7 and a half hours are generally considered appropriate. However, the elderly often sleep less than 6 hours. According to the analysis of EEG, the abnormal sleep of newborns accounts for about 50% of the total sleep time, and it enters the abnormal phase period soon after falling asleep. The adult accounts for about 20%, while the elderly account for less than 20%. In adults, if the time of abnormal sleep is less than 15% or more than 25%, it is considered abnormal. Similarly, the slow wave phase 4 also gradually decreased with age. As for the cycle of sleep and wakefulness, newborns are about 5 to 6 times a day, babies are gradually reduced, and school-age children sleep about 1 to 2 times a day. Some older people return to the habit of sleeping several times a day.

The default "sleep time" of the "biological clock" is to "wake up" 6-8 hours after sleeping; and when to "sleep" is not the most important. And as long as you "sleep", those "physiological activities" that will occur after sleep will still proceed, or: as long as your "sleep time" is enough, no matter when you start to sleep, it will not Affect your "physical health"; and "work and rest time" is just a "habit" and can be changed at will. Of course, it still takes a certain amount of time to form a new habit, usually 3-6 days, so it is best not to alternate this habit too frequently.

Sleep time varies from person to person, although the average adult sleep time is eight hours a day, but in fact, enough sleep is not from the time of more or less, but depends on whether you can achieve a state of deep sleep, experts suggest that the sleep time should generally be maintained for 7 to 8 hours, depending on individual differences. If it is true that people who fall asleep fast and sleep deeply, generally have no dreams or few dreams, sleep for 6 hours can completely restore their energy, of course, it is not impossible. However, those who fall asleep slowly and lightly, sleep more and dream more often still have difficulty refreshing their spirits even if they sleep for 10 hours. Various treatments should be adopted to obtain effective sleep. Simply prolonging sleep time is not beneficial to the body.

Prolonged sleep

American scientists have shown that delaying class time can help improve the effect of learning, and the later the class time, the better.

Biological studies have shown that people tend to go to bed early and get up early in childhood; when people enter adolescence, the circadian rhythm will change, causing adolescents to sleep later and get up later. This change is caused by changes in melatonin in the brain, a process that begins at about age 13, increases significantly at age 15 to 16, and peaks at age 17 to 19. If the class time is adjusted to 8:35 a.m. or later, after one semester, the students' math, English, science and sociology scores are generally improved by 1/4 grade, for example, from B to the middle position between B and B.

A number of studies have shown that students in schools that change their school hours from 7:30 to 8:00 have a greater improvement in academic performance than schools that change their school hours from 7:15 to 7:45 in the morning. Studies from Brazil, Italy and Israel have reached similar conclusions. The key to these benefits is that teenagers get at least eight hours of adequate sleep, and even better if they get nine hours. In Europe, by contrast, few middle schools start classes before 9 a.m.

scientific research

Sleep has three major characteristics, periodicity, spontaneity and reversibility, and with the animal's quietness and decreased sensory sensitivity as a measure, the higher vertebrates began to appear sleep behavior and EEG changes. In fish, amphibians and reptiles, cycles of wakefulness and sleep can be observed, but not heterogeneous sleep. To warm-blooded animals and birds, there is a clear paradoxical sleep, about 3 to 5% of the sleep time. Mammals, from mice to elephants, have well-defined slow-wave and out-of-phase sleep, although their respective proportions vary by species. From the perspective of animal survival competition, it can be roughly divided into two categories: one is that predators, such as rodents, herbivores and ruminants, need to chew for a long time after eating, thus shortening sleep time and short abnormal sleep, generally not exceeding 5%, such as 1.6 for cows, anteaters have no abnormal sleep; The other is predators, such as carnivores, which eat quickly, there is more time to sleep, different phase sleep is also longer, up to 20% or more, such as cats, dogs and so on.

The experimental deprivation of sleep in humans or animals is a feasible way to study the physiological significance of sleep and its necessity.

After 24-48 hours of total sleep deprivation, the EEG frequency slows down, approximating the first phase of the slow wave phase, but the appearance and behavior are normal. Continued deprivation reduces alertness and, in severe cases, hallucinations, delirium, or somniloquy may occur. 3~4 days later, let it fall asleep, in the first night in the slow wave phase 4 significantly increased, and the corresponding reduction of heterophasic sleep, in the next few nights, heterophasic sleep only compensatory to increase. A case of 11 days of sleep-free youth, after falling asleep, slow wave phase 4 and out-of-phase sleep are significantly increased. In contrast, sleep-deprived cats had an increase in heterophasic sleep at night 1, rather than slow wave stage 4 sleep.

Partial sleep deprivation. The subjects slept only 3 to 4 hours a day, and after a few days, the heterophasic sleep or points increased more than the first 4 hours of normal sleep. After the experiment was stopped, the subjects had multiple heterophasic sleep for several consecutive nights. In the long-term sleep only 4 hours a day in the subjects of slow wave phase 4 increased, the third phase of the corresponding decrease. There was no significant change in the slow wave phase during sleep recovery. If the subject's sleep is shortened to less than 3 hours, it will affect the development of stage 4 sleep, which will seriously affect the subject's ability to work.

Choose a certain period of sleep deprivation. If you choose to deprive the fourth stage of slow wave sleep, you will only increase the fourth stage sleep in the recovery process. If you choose to deprive heterophasic sleep, the same compensation will also occur. Many psychological experiments show that long-term deprivation of heterophasic sleep will not produce obvious psychological disorders. However, people who are deprived of all sleep for a long time cannot work for a long time, otherwise there will be more mistakes. This may be related to the inability of the cerebral cortex to maintain a state of vigilance for a long time. In addition, temporary hallucinations and absurd behaviors occur in a small number of people. In short, these experimental results do not seem to support the hypothesis that long-term sleeplessness or severe insomnia can lead to psychopathy, but on the other hand, it shows that long-term lack of sleep can easily cause fatigue, inattention, and visual and tactile confusion.

On September 17, 2014, researchers found that the lateral facial region has a special neuron that specifically produces the neurotransmitter gamma-aminobutyric acid (GABA) to promote deep sleep. They have developed a new set of tools that can remotely manipulate these neurons to manipulate the opening and closing of neurons for research.

"New molecular biology methods allow people to precisely control the function of the brain at an unprecedented level." "Before developing this tool, we usually used electrical stimulation to activate the target area, but this usually affects the surrounding area and does not need to be stimulated at the same time," said Chris Taylor Anselet, a postdoctoral researcher at Harvard Medical School."

Dolphins do not sleep, they will be left and right brain alternate use, better avoid predators. Animals sleep for the same reasons as humans.

morbid sleep

Insomnia

Loading According to the time sequence of insomnia occurrence, 3 kinds of insomnia can be distinguished. ① Occurring in the early stages of sleep, it is difficult to fall asleep, and it is also the most common insomnia. The performance of the whole night when awake and sleep. ③ Occurring at the end of sleep, the patient wakes up prematurely and can no longer fall asleep. These patients have less heterophasic sleep and are prone to evoke EEG arousal responses. From the EEG analysis wave, their sleep time is always more than the chief complaint, the consequences of insomnia is not serious, long-term insomnia sometimes listlessness, available drug treatment to correct. In the clinical treatment of the above, the use of western medicine oryzanol in the integrated treatment of Western medicine can be achieved fast, the ideal effect.

Polysomnia

The performance of the daytime sleep or doze too much, or sleep too long at night. The patient's heart rate does not slow down during sleep, indicating that the patient is not sufficiently rested during sleep. Primary hypomnia is mostly a genetic disease, which is related to hypothalamic dysfunction. In addition, there is a hypersomnia with hyperphagia, obesity and respiratory insufficiency.

narcolepsy

The attack occurs when the patient falls asleep suddenly and cannot control himself, but lasts only a few seconds to a few minutes, and is often accompanied by a cataplexy produced by a loss of muscle tone. The similarity of brain waves and heterophasic sleep during seizures is mostly congenital. Central stimulants can reduce their symptoms.

Sleepwalking

This disease occurs in the third and fourth stages of slow wave sleep, which is also the period with the lowest recall ability. It has nothing to do with the patient's dreams. During sleepwalking, the brain is less alert and reactive, and movements are less coordinated.

Enuresis

Most of them occur in the first 1/3 period of sleep, and the brain waves are slow wave stage 4. Enuresis begins to transfer to stage 2 or 1. After awakening, patients do not complain of dreams. If they do not, they believe that there is an ascending inhibitory system in the medulla oblongata and pons, and the activity of this system can cause sleep. On the one hand, this system receives sensory afferent impulses from the body and viscera, and on the other hand, it is under the downward control of structures such as the cortex of the piriform area, cingulate gyrus and preoptic area of the forebrain. At the same time, M. Jovel proposed the monoamine theory of the wake-sleep cycle. He believes that the ascending noradrenergic system from the anterior part of the locus coeruleus maintains the electrical activity in the awakening state of the cerebral cortex, and the activity of the acetylcholinergic system can complete the advanced functions such as attention, learning and memory. The dopaminergic system of the substantia nigra-striatum loop maintains the behavior of awakening. As for the sleep process, the ascending serotonergic system from the anterior part of the raphe nucleus group maintains slow wave sleep, once the mid-segment nucleus group triggers cellular activity in the locus coeruleus, the latter's upward impulse activates the electrical activity of the cerebral cortex, making it appear fast-frequency and low-amplitude waves, while its downward impulse inhibits the spinal motor system, thus forming heterophasic sleep. But the authors do not say how sleep begins. It should be noted that there is no fundamental difference between the two hypotheses. Because they only argue about the parts of the brain structure associated with sleep. It is along these two scenarios that much of today's work is developing in depth. Since the 1970 s, Monier and J.R. Papenheimer have extracted polypeptide substances from the brains of sleeping rabbits and sheep respectively and injected them into the ventricles of another animal to induce δ waves, which are similar to slow wave sleep. This discovery opens up new avenues for the study of sleep mechanisms.

Sleep is extremely important for brain health. Minors generally need more than 8 hours of sleep and must ensure high quality. If the sleep time is insufficient or the quality is not high, it will endanger life or have a negative impact on the brain, brain fatigue is difficult to recover, serious may affect the function of the brain. If teenagers lack of sleep or poor sleep quality, they should appropriately increase the time of sleep, such as taking a nap in summer, and try to improve their sleep conditions.

According to the general view, sleep is the main way to eliminate brain fatigue. If the long-term lack of sleep or sleep quality is too poor, it will seriously affect the function of the brain, and people who are originally very smart will become confused. Many young students suffer from neurasthenia and other diseases, often caused by severe lack of sleep.

Insomnia hazards

Physiological experiments have shown that people who lack sleep not only have a greatly reduced immune ability, but the daily aging process is 4-5 times that of normal people. The following is a systematic discussion and research on the impact of sleep on physiological tissues:

Sleep and Cell Life

The consequences of lack of sleep on cell oxidative renewal, which mainly leads to tissue damage, this process is through the role of enzymes to repair, for the continuous repair between molecules and the overall maximum life of cells is inseparable, on aging, the most important detection of DNA damage and repair them, and the integrity of the cell is the basis of its division and proliferation of life, and this repair mechanism is completed in the life of high-depth sleep.

Scientific research experiments have shown that high-intensity sleep time is the average body spent on repairing DNA damage to the largest, in the cell molecular, DNA damage and DNA repair between this balance is the most important indicator of cellular aging.

2. Sleep and immunity

Whether it is lack of sleep, or lack of complete sleep, for the body's immune system is a collapse of the blow, the body's thymus will be sharp atrophy. This is the most important immune organ of the human body. Under normal circumstances, only in middle-aged and old age, the thymus will shrink to the size of a cherry, and the value-added of T cells will be greatly reduced, not only a large reduction in white blood cells and lymphocytes, but also macrophages. The cell has an inhibitory effect.

Under the protection of the human body's lack of immune system, the threat of various carcinogenic diseases to the human body can be said to be fatal. Even in the short term, the human body will feel sick, dizzy, mental atrophy, and weak limbs. This is not only a physiological trend of direct decline in immunity, but also a precursor to disease.

3. Sleep and Nervous System

The nervous system is the main functional regulation system of the body, which directly regulates the functions of various organs and systems in the body, and the relationship between sleep and the physiological role of the central nervous system is closely inseparable,

As a regulatory mechanism, sleep is through the hypothalamus is used to regulate visceral activity and hormone endocrine, and neuroendocrine depends not only on the instructions of the central nervous system, but also the activity cycle of the "biological clock" of life.

From a physiological point of view, the biological clock is the memory code in which DNA plays a genetic role. For example, hypothalamic tissue secretes reduced glutathione, superoxide dismutase (SOD) and so on at about 10:00 at night during deep sleep. These are non-synthetic essential hormones, which are mainly used to repair cell damage, promote cell proliferation and differentiation, and ensure the normal growth and development of various tissues and organs.

4. Sleep and repair mechanisms

Experiments have shown that even short-term lack of sleep and lack of enough sleep time, the human body will rapidly age and greatly reduce immunity.

Deep sleep at night, through the role of the nerve center of the hypothalamus, is actually regulating the metabolic activities of various tissue cells to affect the physiological activities of the human body, mainly used to repair cell damage and restore the integrity of tissue function.

The biological clock is controlled by the brain's hypothalamic suprachystic nucleus (SCN), which sends "time signals" to the central nervous system through the secretion cycle of endocrine hormones, thus affecting the biological effect of the body's time. This shows that the body's repair mechanism must be carried out at night.

5. Sleep and Growth Hormone

Sleep is a biological instinct. When people sleep, the muscles of the whole body relax, the reaction to external stimuli is reduced, and the heartbeat, breathing, excretion and other activities are reduced, which is conducive to the recovery of various organs. The body's biological clock governs the endocrine system, releasing various hormones. Among them is a kind of growth hormone, its role is to promote muscle metabolism, restore physical strength, promote bone growth.

In childhood, the secretion of this hormone shows a pattern of more nights and less days. The growth hormone released between 1 pm and 5 am is almost three times that of the day. Obviously, if infants and young children sleep late for a long time, it will affect the normal physiological secretion of growth hormone, which is quite unfavorable to growth and development, especially to height.

Adults who often stay up late are prone to aging, while children are emotionally unstable. It is often said that the waist, legs and feet are sore, do not like to walk, and their eyes are easily tired. Some children are also prone to diseases such as tracheitis and rhinitis.

Often staying up late may also lead to constipation, of course, this has a great impact on the body.

Therefore, for the healthy growth and development of infants and young children, parents should arrange regular work and rest time for them, develop the habit of sleeping regularly at night, and ensure adequate sleep time. The new baby's "night cry" affects the growth of newborn babies. It can be said that there is no difference between day and night. When they wake up, they eat, and when they are full, they sleep. It takes 4 to 5 months to gradually form a rule. By 7 to 8 months, 80% of babies wake up during the day (occasionally sleep) and sleep at night, approaching the adult's life pattern by the age of 1.

6. Creative thinking that affects the brain

Researchers believe that if the human brain wants to think clearly and respond sensitively, it must have enough sleep. If the brain does not get enough rest for a long time, it will affect the brain's creative thinking and ability to process things.

7. Affect the growth and development of adolescents

The growth and development of adolescents in addition to genetic, nutrition, exercise and other factors, but also with the secretion of growth hormone has a certain relationship. Growth hormone is a hormone secreted by the hypothalamus, which promotes the development of bones, muscles and organs. Because the secretion of growth hormone is closely related to sleep, that is, there is a large peak of secretion after sleeping, followed by several small peaks of secretion, while in the non sleep state, the secretion of growth hormone is reduced. Therefore, teenagers to develop well, grow tall, sleep must be adequate.

8. Affect the health of the skin

The reason why people's skin is soft and shiny is to rely on the capillaries of the subcutaneous tissue to provide adequate nutrition. Lack of sleep can cause skin capillary stasis and circulation obstruction, making skin cells unable to get adequate nutrition, thus affecting skin metabolism, accelerating skin aging, and making skin color appear dark and pale. Especially black eye circles, and prone to wrinkles.

9. Lead to disease

Frequent lack of sleep will make people feel anxious and anxious, and reduce immunity, which will lead to various diseases, such as neurasthenia, colds, gastrointestinal diseases, etc. Lack of sleep can also cause an increase in blood cholesterol content, which increases the chance of heart disease; the body's cell division is mostly carried out during sleep, and lack of sleep or sleep disorders will affect the normal division of cells, which may produce cancer cells. Mutations lead to cancer. Generally speaking, people of different ages need sleep every day. Middle school students should sleep 8-9 hours a day and adults need to sleep 7-8 hours a day.

10, lack of sleep can cause obesity

Studies have shown that lack of sleep can lead to a decrease in the concentration of lipoproteinin in the human body. Defatting protein is a substance active in the blood system. It has the function of suppressing appetite and can influence the brain to make decisions about whether to eat. Lack of sleep can also cause an increase in the concentration of appetite hormones in the body. Appetite hormone is a substance secreted by the stomach, which can cause people's desire to eat. When these parts of the body that control "appetite power" conflict with each other, the brain's decision-making system may make the wrong decision.

If people can maintain a normal sleep time, it is possible not to confuse the appetite supervision department in their bodies, so as to keep their weight within a relatively normal range.