Sleep is the most basic instinct of animals. As early as more than two thousand years ago, there were sleeps in classic works such as Neijing. Although people’s interest in and discussion of sleep lasted for thousands of years, it was truly scientific. The research did not begin until the second half of the nineteenth century.
After entering the twentieth century, many scientists have studied sleep from different angles, mainly because researchers stayed in bed at night to observe and record sleep. An epoch-making breakthrough in sleep research in 1953 was the discovery of rapid eye movement (REM) sleep, during which year American researcher NKLEITMAN and his graduate student Arthurinsky (E. ASERINSKY) reported for the first time that sleep consists of several stages. In some stages, the eyeball spontaneously appears to have a continuous and irregular rapid round-trip movement. At this time, the performance of brain waves is different from other sleep stages. From then on, people began to understand that sleep is not just a simple passive state, but a regular periodic change of different phases, different psychological and physiological phenomena. It is an active physiological process, which is the essence of sleep. With a more accurate understanding, sleep research is really on the right track.
Slow and fast waves of sleep. In the 1950s, Kleitman and Artellinski discovered that after a quiet sleep, "active" phase sleep accompanied by the rapid rotation of the eyeball. According to the changes of electroencephalogram (EEG), electromyography (EMG) and electromyogram (EOG) during sleep, the sleep process can be divided into two major phases: slow wave sleep abbreviation (SWS) and Fast Wave Sleep Abbreviation (FWS). Slow wave sleep is also called light sleep. Fast wave sleep is also called deep sleep. Slow wave sleep is divided into 1-4 stages. Therefore, slow wave sleep has deep and shallow points. If the muscles are not relaxed, this is light sleep, slow wave 1— The process of the 4th phase is from shallow to deep. The first phase is a snoring and shallow sleep, which still responds to external stimuli. The second phase of the moderate sleep period has no response to external stimuli. The third phase is moderate to deep sleep. The fourth phase is to fully enter the deep sleep period.
A harbinger of disease found in sleep.
Some people grind their teeth while sleeping at night, which is related to reduced saliva in the mouth during sleep and lack of lubrication on the surface of the teeth. Long-term molars can cause enamel wear on the tooth surface and affect the chewing function. There are many reasons for causing molars. Children play unrestrained during the day, disrupting normal life patterns and affecting sleep, and involuntarily grinding their teeth; being reprimanded during the day leads to mental stress and excessive fatigue, which causes the brain to manage the part of the masticatory muscles in an excited state. Do chewing. If the child can work and rest, and the spirit is happy, these habits of grinding will gradually improve. Other children suffer from tsutsugamushi disease. Due to the disturbance of the mites, the intestinal wall is constantly stimulated, which also causes the reflective contraction of the masticatory muscles to cause the molars. This requires the grinding phenomenon to disappear after the drug is dewormed. Some children eat non-digestible food before going to sleep, so that the digestive tract can not get enough rest, and teething will occur. Therefore, it is not advisable to give your child a non-digestible food or eat too much snack before going to sleep. Children's molars should be taken care of by parents, looking for the cause of molars, active examination and treatment, and making children grow healthier.
Some people drool when they sleep at night. Normal people can secrete a total of 1000-1500 ml of saliva per day. Even in the absence of food stimulation, 0.5 ml of saliva can be secreted per minute. Therefore, when people sleep, a small amount of saliva is continuously secreted to smooth the oral mucosa to protect it. tooth. Under special circumstances, such as dreaming of delicious food, it will stimulate the secretion of saliva, and the secretion of saliva will increase, which will lead to drooling; improper sleeping can sometimes cause drooling; some people often sleep and grind their brains, stimulating the nerve center of the brain. It promotes the secretion of saliva, so that it is drooling; some people love to eat spicy food or smoke, alcohol, so that the mouth dry at night, the secretion of saliva increases; when breathing, mouth breathing is easy to dry the mouth, thereby promoting the secretion of saliva; Some diseases, such as infectious stomatitis, toothache, mercury, potassium iodide poisoning, etc., can also stimulate the secretion of saliva, causing sleep drooling.
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