Scientists are puzzled: why do creatures sleep? Why would you die if you were deprived of sleep?

Sleep is considered among the most important needs of the human body, and one of the most prominent commonalities between it and all living organisms, but scientists are still trying to this day to determine the basic biological function of sleep and are doing many research and studies in this field.

in a a report Published by the French newspaper “Le Figaro”, writer Cecile Tiber says that the sleep in which we spend a third of our lives still holds many mysterious secrets and raises many questions about why it is needed and its effect on our bodies and brains.

We still have a lot to discover about sleep, says Nadia Josselin, a professor of psychology at the University of Montreal in Canada who researches sleep disorders, as there are many hypotheses and no scientific consensus yet.

One of the easiest ways to understand why we need sleep is to observe what happens to the body when we are deprived of it. In 1963, Randy Gardner, who was 17 at the time, stayed awake for 11 days and 25 minutes as part of a science project he was doing with his classmates.

After that period, he appeared to have some disturbances in memory and behavior, in addition to difficulties in concentrating, slowing down in speech, and some hallucinations. At the end of this experiment, Randy slept for 15 straight hours and then regained all his abilities. Later, Guinness World Records abandoned the longest sleepless challenge due to potential health risks.

Sleep is one of the most important human needs, and it is the common denominator between it and living organisms (Shutterstock)

Sleep or die?

Laurent Saunier, a researcher at the Center for Neuroscience Research in Lyon, says this type of experiment cannot be done in humans for ethical reasons, as its after effects are not clear.

To date, there have been no officially known cases of death due to sleep deprivation in humans. As for animals, in 1894, the Russian doctor Marie de Manasin deprived a number of dogs of sleep, which led to their death, and that was the first study to prove the vital nature of sleep. A century later, psychiatry researchers from the University of Chicago in the United States deprived 10 mice of sleep, and this led to their death.

Saunier explains that scientists noticed problems with temperature regulation and a disturbance in the immune response when the animals were deprived of sleep, but in return they found that the animals’ brains were in a very good condition, and there were no clear causes of death.

Sunnier is currently working on the study of sleep in fruit flies, one of the most widely used animals in biology, and explains that the reason for studying these insects is that they are among the simplest animals in terms of nervous regulation, and the goal is to try to discover the original function of sleep.

“If you deprive an immature fly of sleep, it will be unable to learn for the rest of its life,” says Saunier. “When an adult fly is deprived of sleep for 24 hours, it regains its normal abilities after two hours of sleep.”

A popular theory is that the function of sleep is to conserve energy (Shutterstock)

Energy saving

A popular theory is that the function of sleep is to conserve energy, and Jocelyn explains that the period of sleep is accompanied by a decrease in metabolism, and thus a decrease in energy consumption.

But many scientists believe that this hypothesis is not convincing, because sleep provides the equivalent of calories in a glass of milk. Saunier stresses that if the role of sleep was to provide energy, it would have been possible to have enough rest without sleep, instead of losing consciousness for long hours, with the attendant risks, especially since the brain consumes in the dream stage the same amount of energy that it consumes in wakefulness.

Jocelyn adds that another hypothesis is what is known as the detoxification theory, meaning that the brain during sleep hours eliminates toxins accumulated during waking hours.

Although the brain represents only 2% of our body mass, it consumes about 20% of our total energy, and this consumption is accompanied by the production of waste products, including free radicals, tau proteins and amyloid, the presence of which in the form of plaques causes the death of neurons, which leads to Alzheimer’s disease .

Saunier stresses that because the brain is constantly occupied during wakefulness, it takes advantage of hours of sleep to get rid of accumulated toxins, especially amyloid proteins. But the detox hypothesis does not fully explain the essential function of sleep, as the brains of insects, for example, are not equipped with the system that allows toxins to be excreted.

During the night the brain does something like updating, compressing files and getting rid of unnecessary information (Shutterstock)

What happens to the brain?

Another theory is based on the idea that the brain works like a hard disk, and during daylight hours it collects various information, which leads to an increase in the size of synapses, some of which are of no use.

It is estimated that each neuron in the human brain contains about 10,000 synapses at one moment in time, and over time these points become larger and more numerous. “If this growth continues continuously, the brain will not accommodate it,” says Saunier.

According to this hypothesis, during the night the brain performs a similar process of updating, compressing files and getting rid of unnecessary information.

Jocelyn explains that sleep strengthens some synapses and eliminates others that are less important, which allows us to sort all the information we receive during the day.

Scientists believe that sleep works to store information, experiences and situations that we experience during the day in long-term memory. “We believe that the information we receive throughout the day is stored first in the hippocampus, an area of ​​the brain largely responsible for short-term memory,” Jocelyn says. “For long-term storage, we must transfer it to other areas of the cerebral cortex, and we think that sleep It enables us to make this transition.”

Sleep is also known to play a role in brain maturation during childhood, as well as strengthening the immune system. Some scientists believe that sleep helps replenish a store of useful molecules for the brain during the day, in addition to releasing hormones needed for cell repair and growth.

Leave a Reply

Your email address will not be published. Required fields are marked *