1. Sleep period: it is a transitional period between waking and sleeping, and people wake up very easily, accounting for about 10% of the total sleep time.
2, shallow sleep period: this period is easy to wake up, people who have difficulty falling asleep often wake up on their own, accounting for about 50% of the whole sleep period.
3. Midsleep: During this period, consciousness disappears and it is not easy to wake up, and each sleep cycle lasts about 1 hour.
4, deep sleep period: this deep sleep period, awakening is quite difficult, each sleep cycle lasts about 30 minutes, and then enter rapid eye movement sleep.
In the whole sleep cycle, SWS and REM appear alternately regularly, and each of the two kinds of sleep at different times has a sleep period. Each cycle lasts 70 ~ 90 minutes, and you must go through SWS stage to enter REM.
Sleep is divided into five periods. During the 8-hour sleep every night, every sleep cycle is repeated every 90 minutes. The first four stages are non-rapid eye movement sleep (NREM) or slow wave sleep (SWS), and the last stage is rapid eye movement sleep (REM).
SWS is the whole process from hazy sleep to deep sleep. The EEG at this stage is slow wave and there is no eye movement, so it is called non-rapid eye movement sleep.
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Tips for falling asleep:
1, don't sleep with the light on: Although people close their eyes when they sleep, the light will still be perceived by the human body. ?
2. The bedroom environment should be clean and quiet: the room should be clean and hygienic, with good air circulation, suitable room temperature and quiet environment. Bedding should be suitable, soft, light and comfortable, often aired, frequently dismantled and washed. The height of the pillow should be properly selected. Generally, the height of the adult pillow is 5-8 cm, and the pillow core is made of buckwheat husk and chaff with high permeability and good fluidity.
3, emotional stability: avoid anxiety and anger, calm, calm. Don't watch thriller detective books, movies or TV before going to bed.
4, do not eat before going to bed: eating before going to bed increases the burden on the stomach and intestines, and it will also make people feel full, which not only affects sleep, but also easily leads to obesity. In addition, strong tea, coffee and wine should be avoided at night. Drinking a cup of hot milk or listening to music before going to bed is helpful to relax and fall asleep easily.
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