Why do we sleep? What is the real purpose of having it? what is happening while we sleep? In scientific terms, researchers find, it is to enable both our mind and body to recover.
We need sleep for surviving, just like other essentials; food, and water. So, normally we spend about one-third of our lives on it. Also, it affects our physical and mental health. The amount of sleep we have can directly affect our emotional balance, physical energy, productivity, and even for the body weight.
Biological processes that happen during having nap
- Brain restoring: brain gets rid of toxic waste and restores memory.
- Brain functioning: Nerve cells reorganize, and communicate with each other which supports healthy brain function.
- Restoring physical energy.
- Cell repairing: body repairs cells, and releases hormones and proteins.
What happens when we sleep?
During sleep, our body goes through four sleeping stages. This cycle occurs multiple times throughout the time in different lengths. The cycle includes two major phases:
- Non-rapid eye movement (non-REM) sleep.
- Rapid eye movement (REM) sleep.
As the names describe themselves, non-REM sleep features an absence of eye movements, whereas REM sleep, is characterized by rapid eye movements when dreaming occurs. These four stages contain three stages of non-REM and one stage of REM.
Stage 1: occurs at the first moment of falling asleep. While the body enters light sleep, brain waves, heart rate, and eye movements gradually slow down.
Stage 2: features just before the deep sleep. In this stage, body temperature decreases, fewer eye movements, and heart and muscles continue to relax. Also, there is a clear slow down at the spikes of the brain waves. This is the longest stage among all the 4 stages.
Stage 3: This is stage includes deep sleep. Here, our eyes and muscles stop their movements, and further, brain waves slow down. Important thing is, our body restoring its energy and repairs cells and tissues. To gain a fresh, alive next day we need to complete this stage.
Stage 4: This is the dreaming stage that happens about 90 minutes after we fall asleep. Here in REM phase, eyes move quickly from side to side.
What happens in REM sleep is, our brain waves and eye movements increase. And heart rate and breathing also speed up.
Apart from dreaming, our brain processes information during this stage, it is important for learning and memory.
Researches make clear that sleep is essential at any age in different amount. Some people have conditions that result in changes in the way they sleep, called sleeping disorders. Also, some are not getting enough sleep, due to their life pattern. Both of these conditions associated with increased health risks and damages. For example, drowsiness can contribute to serious car accidents and even deathly injuries.