Mis à jour : 9 sept. 2020
Biologically Sleep is like oxygen. It's not optional.
Sleep is when your brain shuts down so it clean out garbage chemicals that have accumulated over the day. Also it re-arranges and cleans recent memories, which occupy a lot of neurons, cleaning out those memories which are irrelevant and storing those memories that deserve to be in long-term storage. Probably many dozens of other functions happening, both information processing and chemical processing.
Important to remember that your brain is the highest-maintenance, high-performance, most energy-intensive parts of your body.
The "algorithm" that brains use for all this maintenance is no doubt wonderful and extraordinary and I can only hope one day scientists begin to understand it all.
Without sleep for too long a time, your brain literally begins to fail, chemically. Your memories and judgement gets jumbled and incoherent, your personality starts to fall apart. After many, many days without sleep, you die, because your brain stops functioning.
I'd like to take this moment to say, people who routinely "skip" a full nights sleep are destroying their health and their intelligence, and are kidding themselves if they think it's improving their performance.
Different Theories about sleep
1. Inactive theory:
This relates to the adaptive or evolutionary theory where sleep acts like a survival function to prevent any harm for the organism. The theories suggest that animals who could stay still (sleep) were less vulnerable than those who were active all the time.
2 Energy conservation theory:
One of the best competitive advantages in society is the acquisition of efficient energy utilization techniques. The energy conservation theory suggests that the primary function of sleep is to reduce the individual’s demand on its energy expenditure, allowing it to conserve energy for other times.
According to a 2016 review in the journal Sleep Medicine Reviews, during certain phases of sleep, the brain consumes only about half the glucose as it does when a person is awake. (Glucose is the sugar that cells burn up to release energy.) This supports that energy metabolism is significantly reduced during sleep. But, again this is related to the inactive theory in many ways.
3. Restorative theories:
Another theory serves to explain the body tries to restore what is lost while we are awake.
· The most striking example of this theory is seen in sleep deprivation research. Rats totally deprived of sleep, lose their immune function, and die within two or three weeks
Why do people need to sleep?
Most notable is the case of Randy Gardner., Gardner is the world record holder for the most amount of time a human has intentionally deprived themselves of sleep. In 1965, then a 16-year-old high schooled, Gardner stayed awake for 11 days and 24 minutes. At the end of the stunt, his speech was slurred, his thinking was fragmented, and he wasn’t able to perform simple math for longer than a few minutes’ time.
The brain rejuvenates during sleep as well. For example, while we are awake, neurons in the brain produce adenosine.
A toxic by-product of the cells' activities. The build-up of adenosine in the brain is thought to be one factor that leads to our perception of being tired. However, this feeling is counteracted by the use of caffeine, when it blocks the actions of adenosine, and helps keep our brains active.
Thus, during sleep, the body has the chance to sweep off the excess buildup of adenosine and other such toxic products, and as a result we feel more alert when we wake.
4. Brain Plasticity theory:
This is one of the most promising explanations for why we sleep. Sleep is actually correlated with structural and organizational changes in the brain. Brain connectivity and plasticity are involved in learning and consolidation of facts, experiences and memories.
· Sleep Medicine reviews outlines in its research paper that when animal learn a new task, the neurons strengthen synaptic connections involved in learning that task during the following sleep cycle.
This helps us transfer bits and pieces of information from short term memory to long term memory and consolidate our memories. Thus, sleep is not really the lazy and lackadaisical slumber that people imagine it to be. Its an active process where our memories are consolidated and concretized
Sleeping is a biological activity. In scientific terms, sleeping is behavior. No different from behavior like driving a car or texting on your cellphone. Sleeping is just a million times more important behavior than those to stay healthy.
Driving and texting cannot become “disordered”, nor can any other activity like e.g. sleeping. You can do activities right or wrong, efficiently or inefficiently, you can perform activities sufficiently to reach your goal or insufficiently, but you’re driving, texting, or anything else you do can never ever become sick, diseased, or disordered.
Every so-called “sleep disorder” is in fact no “disorder” at all but rather lousy sleeping (like lousy driving or lousy texting) - in case of “Insomnia”, it is super-lousy sleeping. Consequently, since scientifically there are no sleep disorders, there cannot be any strange sleep disorders most people wouldn’t know of, unless a medical professional or psychiatrist invents yet another new one, which probably would not be much more beneficial to humanity, I’d think.
Sleeping lousily is a very serious health risk, though. However, there is only one way to improve it: Learn how to do it better. Learn what you - and only you yourself - must improve when awake to sleep better.
Any less-than optimal sleeping is just lousy sleeping. It’s always the consequence of lousy sleep hygiene and lousy stress and anxiety relief skills, of what you do or don’t do when awake, and of how you arrange your sleeping-workshop, your bedroom. Nothing “disordered” about that at all; sleeping issues are always simply the non-negotiable consequence of an inaccurate awake lifestyle.
Scientifically four main stages that you go through during the sleep process:
1. stage 1, you grow more relaxed, passing from conscious to unconscious. You’re breathing and heart rate slows down, your eyes starts to roll. You start to drift in and out of a light sleep, and can be wakened easily. If wakened, you make believe that you have not yet fallen asleep and were awake all the time. After an undistributed period in this stage (about 10 to 20 minutes), you move into stage 2.
2. this stage you are now asleep, although you can still be woken easily. Your eyes are still rolling, and your breathing gets deeper and slower. This stage last about 10 to 20 minutes.
3. You are now in deep sleep. Your brain waves slowly down and your muscle relax more. Also, your heart rate and breathing slows down further and your body temperature drops. Your eyes may roll from side to side. At this point it is difficult to wake you.
4. In stage 4, you are in the deepest level of sleep. Brain waves are slow and large, and your growth hormones work to repair tissue in the body. This stage usually lasts for about 20 minutes. The whole cycle from stage 1 - 4 can take 90 - 100 minutes and will be repeated several times throughout sleep.
After completing this stage, the sleep cycle goes into reverse, working through stages 3 and 2 again. However, when you reach stage 1 again, things are different. The brain waves and breeding are similar, but now you are in a REM (rapid eye movement) sleep. The majority of dreaming takes place here. If you dream out with REM sleep the dream will be mundane, and will seem more like ordinary thoughts rather than dream images.