What Happens In The Different Phases Of Sleep?

Even if you think that some nights you don’t dream, the brain goes through six different sleep phases every night in which it produces dream images.

Sleep is a physiological process that your body needs in order to regularly restore the resources you use up during the day and to carry out the internal functions of the body.  But what exactly happens in the different phases of sleep ?

There are different phases and stages of sleep, but these require the absence of distractions and disturbances that can be caused by external factors.

A few examples of factors that disrupt sleep:

• Tobacco use
• Excessive coffee consumption
• Consumption of alcohol
• Anxiety disorders
• stress

In this article, we’re going to take a look at the different stages of sleep and explain how you can enjoy each of them.

What are the physical stages of sleep?

While your eyes are closed, there are clear electrical oscillations that can be seen on an electroencephalogram (EEG) at an alpha rate of 8-13 per second.

After a few minutes, based on the activity of the brain, the changes associated with each phase of sleep can be marked.

This is how scientists found out what we know about sleep today.

How are the sleep phases divided?

Phase 1

• In this  phase you are a light sleeper. It is a brief stage at which the brain can enter and exit the dream state. You also wake up very quickly.
• In Sleep Phase 1 rapid eye movement (upfront Rapid Eye Movements ) as the muscles are slow, this phase is why REM sleep is called.
• In this phase it is possible to perceive acoustic and sensory stimuli. This sleep phase brings only minimal recovery.

• You may notice that your muscles suddenly twitch at this stage. Because of this, some people sometimes feel like they are falling. This is your perception of the transition from sleep phase 1 to sleep phase 2.

Phase 2

• In the second phase of sleep, the eyes stop moving quickly and the dynamic brain waves slow down until there is only  one single activity of fast brain waves.
• A pattern called the sleep spindle becomes visible on the EEG  .
• In addition to the slow waves, this is also when your  body temperature, heart rate, and breathing slow down.

• At this point,  the nervous system blocks  sensory stimuli,  making it almost impossible to get information from the outside world.
• This makes them a  very restful sleep phase, even though it only happens briefly.

Phase 3

• In this phase of sleep you start to have much slower brain activity than in the previous one. The delta waves are crossed by fast, smaller waves.
• At this stage of sleep, a person usually remains without eye movement for two to three minutes and it can be difficult to wake up.
• The sensory perception is completely blocked. If a person wakes up during this phase, they will feel disoriented and confused.
• During this time there are  no dream images, blood pressure is low, and growth hormone production is increased.

Phase 4

• This phase is almost exclusively characterized by delta waves. It is a stage of  deep, intense sleep that is even more difficult to wake up from.
• There is no eye or muscle movement. When children wet their bed, sleepwalking, or have nightmares, it usually happens during this phase of sleep.
• There are no dreams in this deep sleep. This phase usually lasts  20 minutes.
• Still, it is this phase that determines whether you got a good night’s sleep  or whether it was not restful enough.

How many phases of sleep occur during a night?

People typically switch between REM sleep and non-rapid eye movement at intervals of 70 to 100 minutes.

The phase with rapid eye movement typically lasts 5 to 30 minutes,  the rest of the time being part of NON-REM sleep.

Both cycles  are usually repeated every 1.5 hours  and you can go through four to six cycles of REM sleep in one night.