Probably most of us treat sleep as an activity needed for the body to rest and for us to have strength for the next day of life. Is it so? Not necessarily. The function of sleep is not to conserve the body’s energy. During sleep, the body uses as much energy, and sometimes even more than when we are awake. So what is sleep and what is its function in your life? The fundamental knowledge of sleep is that it is essential to life. Simply put, without sleep we die. Let me start with the fact that sleep is divided into two phases – the NREM and REM phases. The abbreviation REM stands for “rapid eye movement”. Surely you know that during dreams our eyeballs move. The abbreviation NREM means “non-rapid eye movement” – the lack of rapid eye movements. Both phases are essential for sleep. For both phases to fully fulfil their tasks, it is necessary to sleep for at least eight hours at night. If we sleep less, we disturb the natural sleep process and lose a lot. What are the NREM and REM sleep stages responsible for?
Photography Wojciech Laube
During sleep, our brain performs extremely important operations to organize the information that we recorded while awake. Then, the information is sorted into those that are to be forgotten and those that are to pass from short-term memory to long-term memory. This is an extremely important and necessary procedure for our good functioning. Without this process, the limited capacity of short-term memory after a full day of wakefulness is not released. The consequence is that there is not enough space in short-term memory to be able to remember anything for more than a day or two after a night of not fully sleeping. What’s more, if after a not-quite-sleepy night, the next day, we go to sleep for a full eight hours, we will not catch up with the “oversight” of memory. The conclusion is simple: to be able to absorb new knowledge and experience, we need eight hours of sleep at night. If you are a student, yes, you will learn the information for the next day and pass the exam, but this knowledge will not stay with you for more than 48 hours. This, of course, is not the only function of sleep. One of the next essential functions of the brain during sleep is dealing with emotions and social behaviour, which is nothing more than emotional and social intelligence.
Photography Wojciech Laube
During dreams an extraordinary process takes place. This process consists of processing and separating emotions from memorized difficult and strong emotional experiences. You probably know the saying “Time heals all wounds”. Surely you also know firsthand that this is so. The more time passes from the moment of an emotionally difficult experience, the easier it is for us to deal with this emotion and the easier it is for us to face this experience with emotional distance to it. But there is one point that needs to be corrected in the saying “time heals all wounds”, and that is “Time + Sleep heal all wounds”. Time alone cannot heal your emotional wounds. For this you need sleep, and more specifically dreams. What happens during dreams that they soothe the emotions caused by emotionally difficult experiences? Once our brain sorts the information and experiences from the previous day into those “forgotten” and those “to remember” for longer, it introduces us to the phase of dreams. After a difficult emotional experience, we often dream a difficult dream that has something to do with such an experience. This process has the task of separating difficult emotions from this particular situation. Your brain “teaches” you how to deal with that emotion. Over time and in such dreams, the emotional wound heals. The problem arises when we do not sleep for the full eight hours and our brain does not have time to properly deal with it and carry out this particular phase of sleep. Then we have a problem with such a difficult experience and it can cost us many years of emotional problems and psychotherapy. This is one of the big reasons for PTSD: Post-Traumatic Stress Disorder. Science has proven that in the brains of people suffering from PTSD, a certain “switch” that is responsible for separating emotions from a difficult experience does not work. Then there is a situation in which a man, e.g. a soldier after a terrible experience on the battlefield, dreams about this experience every night. The difference is that during such a dream, emotions are not separated from the traumatic experience, and such a soldier relives the trauma every night with the same emotional intensity as when he experienced it on the battlefield. It can certainly be described as extremely traumatic and debilitating
Photography Wojciech Laube
I also mentioned that dreams have an important social function. During sleep, we learn about our own emotions and how to recognize the emotions of others. Through dreams of various situations and emotions, our consciousness receives new packets of information about emotions. This, in turn, translates into the time we spend among other people during the waking state. We are then calmer, we understand more about the behaviour of others and we get along better with the people around us. Another amazing function of sleep is to build creativity. It is a function that might even seem magical. Have you ever told yourself that “I would sleep on it”- to resolve some problems in your life or to make some difficult decisions? I have done it many times.. Everyone knows it, but how does it work? Well, during sleep, your brain has an extraordinary ability to associate facts, situations and emotions and combine them to solve a given problem or create something new. The function differs significantly from the one we consciously have during the awake state. During the waking state, we can connect facts, emotions and situations that have happened relatively recently in time with each other. During sleep, when we are not conscious and when we are completely cut off from the outside world, our brain can amazingly combine it all, almost unlimited time in any way. It extends its network of memory and experience to everything we have experienced and remember from the day we are conscious. Brain in sleep mode can combine the information you acquired yesterday with the fact that you experienced, let’s say … twenty years ago but you have no chance to remember being in awake mode. This is how Paul McCartney composed the song “Let It Be”. As he described this situation, he woke up after a good night’s sleep and then the whole morning he could not stop humming a certain melody. He was convinced it was a tune he had heard somewhere on the radio or at a concert. When he started playing this tune to members of his band (The Beatles), they made him realize that it was something he had invented. Another example is Keith Richards, a guitarist of The Rolling Stones. Every night he went to bed with his guitar and tape recorder ready to record in case he woke up at night with an idea for a new song. This time Keith Richard slept all night, or so he thought. When he woke up, much to his surprise, he noticed that the reels in the tape recorder were spinning and the “record” button was pressed. As he rewound the spools and played their contents, he heard the opening riffs which, as it later turned out, came from the piece Satisfaction – one of the most iconic tracks of The Rolling Stones. While asleep, without any awareness, Keith Richard’s brain composed one of the greatest rock songs of all time.
Photography Wojciech Laube
As you can see, sleep is an extraordinary gift of nature and evolution for man. It is essential for our memory, creativity, social relationships, mental health and many other factors. To be able to take full advantage of these possibilities we must take care of sleep. The most important thing is to sleep regularly eight hours a night. Without it, none of the things I have described will happen, unless we want to suffer mentally and physically. Then I recommend sleeping less. At the beginning I mentioned that without sleep we die … you might wonder why? When our brain cannot take full advantage of eight hours of sleep, to put it briefly, its capacity and thus its functions “clog up”. The brain is not able to process the information that comes to us from the outside world in a correct way, it tries to save itself by force, causing a state of dreams and then we experience strong hallucinations in the waking state. In addition, the brain does not have the processing power to properly manage our entire body. Then, after a long time without sleep, the functions of our internal organs start to fail, the body is chilled, our immune system turns off, and we catch infections from bacterias in our body that normally serve us. The body begins to consume itself to produce heat, oozing sores appear on the skin. In the final sleepless state, we are unable to move, speak, and receive no signals from the outside world. We are like a vegetable mired in delusions and hallucinations until we die.
Sleep is an amazing evolutionary feature. It is one of our superpowers that evolution has endowed us with. It is worth taking care of and developing instead of rushing at breakneck speed at the expense of your own life, mental and physical health. By not caring about sleep, even not sleeping eight hours a night regularly, we can shorten our lives by up to 20 years or more.
So sweet dreams and goodnight.
Dr Matthew Walker “Why are we sleeping”
J.A.Horne B.S. Shackell, “Slow Wave Sleep Elevations after Body Heating: Proximityto Sleep and Effect of Aspirin, “Sleep” 1987, nr 10(4), s. 383-389.
K.Kaida, K. Ogawa, M. Hayashi, T. Hori, Self-Awakening Prevents Acute Rise in Blood Pressure nad Heart Rate at the Time of Awakening in Elderly People, “Industrial Health”, styczeń 2005, nr 43(1), s. 179-185.
- Tochikubo, A. Ikeda, E. Miyajima. M Ishii, Effects of insufficient Sleep on Blood Pressure Monitored by a New Multibiomedical Recorder, “Hypertension” 1996, nr 27(6), s. 1381-1324.