Sleep | What is Sleep and its Stages:

 You would be able to learn in this article:

•     What is sleep?

•     What is the association between sleep and health?

•     What are the consequences of sleep deprivation?

•     What are the types and stages of sleep?

•   What are sleep and wake disorders (Insomnia, narcolepsy,   anxiety insomnia, etc.)

Sleep:

Sleep is a vital health habit, but it is often abused which further leads to different physical and psychological problems. Sufficient sleep risk renewal and relaxation are very much important health behaviors. Many people abuse their sleep intentionally or suffer from insomnia.

Sleep and Health:

A variety of behavioral methods that promote relaxation can offset these risks in addition to setting aside time to savor the pleasant aspects of life and simply taking vacations may have health benefits. We can say that completing the number of hours of sleep can help us to find sleep. We may say that it's a condition of body and mind which typically reoccurs for several hours every night in which the nervous system is inactive, the eyes are closed, the postural muscles are relaxed, and the consciousness practically is suspended.

Types of Sleep:

There are technically two types of sleep

·      Rapid Eye Movement Sleep that is known as rem sleep it's a kind of sleep that occurs at intervals during the night and is characterized by rapid eye movements. There is dreaming, more bodily movements, faster pulse, and breathing take place.

·      Non-Rem Sleep is a dreamless sleep, during the non-rem sleep the brain waves of the EEG recording are typically slow and are of high voltage. The breathing and heart rate are slow and regular the blood pressure is also very low. The sleeper is relatively still.

Stages of Sleep:

1.  In stage one there is the transition between wakefulness and sleep that lasts around five to ten minutes before a person falls asleep.

2.  In stage two, the body’s temperature drops, and heart rate begins to slow, and the brain begins to produce sleep spindles and it lasts approximately about 20 minutes.

3.  In the third stage, the muscles are relaxed blood pressure and breathing rate starts decreasing or dropping down and deeper sleep occurs.

4.  The fourth stage is rem sleep. The brain becomes a more active body, becomes more relaxed, and immobilized dreaming occurs. There is rapid eye movement that takes place.

    This is just another picture to show you that how the sleep cycle takes place. Brain-wave activity varies from the first stage to the fourth stage. There are machines that are available which help in recording these waves. Generally, we use EEG to record the brain waves during sleep. There are different kinds of frequencies and amplitude of these waves for example when a person is awake the frequency in hertz is 15 to 50 and the amplitude microvolts are less than 50.

In stage 1, that is a non-rem stage, and the wave is called alpha-wave the frequency is 4 to 8 and the amplitude is 50 to 100.

At stage 2, there is a theta-wave and there are sleep spindles that are coming. Also, there are k complexes, the frequency hertz is 4 to 15 and the amplitude is 50 to 150.

At stage 3, the brain wave is called delta-wave, the frequency per hertz is 1 to 4 and the amplitude is 100 to 200.

However, in the fourth stage that is rem sleep or rem stage the frequency per hertz is 15 to 30, which is quite like when the person is awake that is 15 to 50 and the amplitude is also less than 50 which is again like when a person is awake.