Until recently it was thought that brain cells are a finite number and they only decrease during human life. It turned out that although most of neurons appear during childhood, in some brain centers they may be formed into adulthood and even in the later years of life.
This process, called neurogenesis, happens in the hippocampus, perhaps the most important area of the brain that orchestrates memory, emotions and learning. There are, however, factors which block neurogenesis and kill brain cells.
Here are the 5 most dangerous:
An adult man must sleep 7-9 hours a day. This is the necessary time for the brain to pass all phases of sleep – from falling asleep during deep sleep to the phase of rapid eye movement under closed eyelids.
This phase is the most important. The brain works hard to keep the person asleep and paralyzes his/her limbs. This is the stage of dreams in which memory is refreshed and memories are arranged in stock. A man who does not sleep enough, is unable to focus, to accept information and make decisions.
A study from 2014 showed that in case of long wakefulness neurons in energy center called locus coeruleus are also dying. Another study found that lack of sleep over the age of 60 cortex and hippocampus shrink. It turns out that a good sleep becomes very important precisely after this age.
By each puff from a cigarette a person engulfs 7,000 toxic substances, 69 of which cause cancer. Smoking leads to other diseases – from chronic bronchitis and emphysema to stroke. Exactly stroke kills brain cells.
A French study in 2002 found that those addicted to nicotine mice formed 50% less neurons in the hippocampus. Accordingly, the higher the dose of nicotine is, the more cells die. Research leader Pierre Piazza wrote in the New Scientist journal: we understand now why smokers who try to quit smoking, have problems with memory. When they smoke, the stimulating nicotine effect conceals the loss of neurons. Once they stop smoking, the deficit occurs.
Delusion that alcohol kills brain cells comes from other processes in the body caused by the alcohol. One of them is called “breaking the seal.” This is the moment when you go to the toilet after you have drunk two beers.
After this moment you start urinating more frequently. The more alcohol you consume, the more synthesis of the hormone vasopressin, which is responsible for water retention in the body is reduced. When its level drops down too much, one cannot hold urine and the result is dehydration. The hangover is a result of this.
And since 75% of the brain is water, every glass of vodka should be consumed not only with tomato juice, but also with a large glass of water. In fact, the abstainer should also have at hand a large glass of water throughout the day. Dehydration occurs in 4 hours. After 8 hours, the brain swells (cerebral edema) because the body sends last water supplies to the brain cells and some of them burst. There are perceptions that due to electrolyte imbalance neurons begin to issue false signals.
According to many people everything goes wrong during one day of the week. Usually this is Monday. So many problems gather in this day, so a man gets stressed. A person tightens, but this has its limits. If these limits are passed, the stress becomes killing for the brain.
The reason for this is hormone cortisol, which in stressful moment is infused into the blood by the adrenal glands. Cortisol redirects the body energy into the body part that currently needs it. If the heart beat becomes faster, let’s say, digestion stops.
Chronically stressed people, however, have the cortisol levels so high, so that the brain stops producing neurons, but increases production of myelin cells. Myelin is a fatty living tissue, the white brain substance consists of it. It speeds up the signals between neurons. These changes, however, can lead to schizophrenia or another mental disorder.
Marijuana does not kill brain cells, but other drugs make it very successfully. The most ferocious killers of neurons are cocaine, ecstasy, amphetamines and so called bath salts (synthetic cathinones). They cause violent release of serotonin and norepinfirin. Man falls into euphoria and becomes overactive, but loses the neurons that are responsible for the synthesis of calming hormones. As a result, the man develops tolerance and addiction to the drug and to achieve its effect larger doses and heavier opiates are taken.