Sleep has always been a fascinating subject for people. No wonder - we also spend a third of our lives sleeping. When something takes that long, we automatically assume that it is important and good.
Even if there has long been a keen interest in the field of sleep research, the functions of sleep are not yet fully understood. However, as time and research methods evolve, some progress could be made.
However, it is safe to say that our sleep affects us a lot - both our bodies and our brains. Use ear muffs for sleeping right away to have a better night's sleep
What changes in sleep
Going to sleep is a natural act for us - we think nothing of it. And that although some things in the body change when we sleep. Basically, many of the vital functions of sleep differ from the waking state.
These include B. the pulse, the respiratory rate and the blood pressure.
Recent studies show that brain activity also changes.
These changes occur in primates and other higher living things in NREM sleep. During REM sleep, the states are more similar to those during wakefulness.
What is REM sleep?
During REM sleep, in addition to rapid eye movements with closed eyelids, other signs also occur: the heart beats faster, breathing and heart rate increase.
In addition, there is a changed activity pattern in the brain, which can be observed with an EEG. Most dreams take place in this phase. REM sleep plays an important role in the processing of memory contents and newly learned things.
What is NREM sleep?
NREM sleep is the exact opposite of REM sleep: Here we are in a dreamless sleep and are usually very calm. Breathing, heart rate, and blood pressure are also low compared to REM sleep.
NREM sleep consists of four different phases that have different depths. We spend almost 80% of our sleep in an NREM phase.
Functions of Sleep - Why Do We Sleep?
The new awareness of the importance of healthy sleep is not old. In the past, sleeping was even considered a death-like condition - but it was certainly seen as comparatively nonsensical.
Today we care about these things because we know that healthy sleep contributes to our well-being. We are also aware that sleeping makes sense - that is, it has a function.
When we talk about functions, we actually mean a mixture of activity and purpose. So what does sleep do for us and what is its purpose?
1. Regeneration of body and mind
Sleep gives our body the opportunity to recover. You could almost say it is our "fountain of youth". In some experiments with rats it has been impressively demonstrated that sleep can even influence wound healing.
Many biologically complex functions occur during sleep such as B. tissue repair or muscle growth - and we don't even notice it.
For this purpose, growth hormones are sent to rebuild muscles or to relieve body parts that were stressed during the day's activities.
In this study, this effect was shown to be particularly strong in men who had a long period of deep sleep. So the more sleep we get, the better the body is equipped to heal itself.
The immune system cannot do without sleep either: after sleep deprivation of 24 hours, rats were found to have 20% fewer white blood cells. These have an important function in the defense against pathogens.
2. Relaxation / refreshment
The idea of having to concentrate 24 hours a day and work is not great. Here our body sets a natural barrier for us! Because he needs a recovery phase so that the following day can also be successful.
Various other parts of the body also recover at night. Because while we sleep, not only do we take a break.
The brain
Our oversized brain in particular needs a chance to relax for optimal performance - it gets this at night.
When you are awake, the neurons in your brain produce a chemical called adenosine. This product makes us tired.
During sleep, the body cleans itself of adenosines. We wake up refreshed and, at best, are no longer tired.
It is completely different with the brain - it works at full speed during the night.
In short, it works to rid itself of toxic by-products that build up during the day.
The body
It works a little differently in our body. During REM sleep, the muscles relax - this leads to relief and reduces symptoms of great tension.
That's why we (usually) feel refreshed and fresh in the morning. Doc
h how exactly does our body do that? Some mechanisms in our body are particularly responsible for this relief:
The body cools down
Our body also needs to cool down sometimes. One of the main functions of sleep is to save energy. This can best be imagined as with various technical devices with stand-by mode. We know the device is connected and yet it is not necessarily turned on. When we sleep we run in stand-by mode. In addition, our body temperature drops by approx. 10 percent to relieve and protect our energy reserves.
Breathing slows down
During the day our breathing pattern is very different. Sometimes we are relaxed or bored. Sometimes we have to hurry and take a deep breath. Every now and then, something even takes our breath away. When we sleep, breathing slows down and becomes very regular.
The heart rate is reduced
Another part of the body that is a little slower to deal with in sleep is our heart. It is very busy during the day and works at full speed. At night, especially during NREM sleep, it takes some pressure off and reduces the heart rate - just like blood pressure.
3. Organize and consolidate memories
We all know this function of sleep only too well. This happens, for example, when we suddenly find content or fragments of our day in our dreams, albeit in a different form.
In our sleep we process experiences from the waking phases. We also process positive and negative experiences and, in the best case, manage to classify them. We have to be able to organize, sort and consolidate memories and learning content.
Even if scientists have already established some connections between sleep and memory, we are in a new area here. This means that the results here also have to be viewed as very experimental.
In the meantime, however, a study has shown, for example, that nerve connections strengthen during sleep when we learn something. These results show that sleep plays a key role in promoting learning-related synapse formation. This is the only way to save learning content.
There is still a lot to learn and research when it comes to sleep and its functions. We still don't know enough about what happens in the body and how it affects us. However, one thing is clear: sleep is extremely important! Especially when it comes to ...
To regenerate our body
To feel refreshed and relaxed
To sort and consolidate our memories or learning content.
