Why does the death of brain cells occur and what are the consequences of atrophy. Does the human brain shrink or, on the contrary, may one day explode from an overabundance of information

British neurophysiologists from Stanford University recently surprised the world with the news that after 40 years the brain begins to shrink. And in people who have lived to an advanced age, the white matter of the brain (that is, the accumulation of nerve fibers extending from neurons and making up pathways) can be as much as in young children.

According to research leader Professor Brian Wandell, areas of the brain degrade differently over the years: in areas associated with the control of movements, the lack of white matter is most felt, and in the lobes responsible for learning, the losses are maximum. The researchers did CT scans on a number of volunteers aged 7 to 85 and found that the most white matter is observed in people 30-50 years old, and this time of life can be safely called the heyday of the brain.

“The number of connections between nerve cells actually increases from the moment of birth until the age of 40-50, and then gradually decreases,” Alexander Kaplan, a psychophysiologist, Doctor of Biology, professor, head of the laboratory of neurophysiology and neurointerfaces at the Faculty of Biology of Moscow State University, explained to Rosbalt. . “These connections, in fact, are the outgrowths of nerve cells, which just create the same white matter (the cerebral cortex, consisting of the nerve cells themselves, looks gray in color), the decrease in the volume of which Stanford scientists say.”

There are fewer neural connections, as the rate of formation of new ones decreases, while the old ones are destroyed due to the fact that they are no longer in demand. Another question is to what extent the reduction in the number of connections leads to a deterioration in the intellectual activity of an elderly person. “Here, the picture is no longer so unambiguous,” notes Kaplan, “because with age, in solving creative problems, people are more and more helped by previous experience than new knowledge. For children who study at school, experience cannot help: in order to master large volumes of new things, they need creativity, good memory, speed of reaction - that is, everything that requires the active growth of new connections. Therefore, those people who have been working effectively in their profession all their lives will not notice the negative consequences of aging of the nervous tissue for a long time. Of course, this will not last forever: some from 60, some from 75, but sooner or later a person begins to feel the so-called deficit of cognitive functions - memory, attention, thinking, and others. It's such a total process. But the variations between people are very strong: it all depends on the genetic potential of a person and on his life experience. And this means that the “shrinking” of the brain is not a sentence, but a guide to action.”

Trying to finally decipher the secrets of the main organ of the human body, scientists from Great Britain, Japan, the USA, China and the EU decided to artificially create complete model human brain. The researchers say they intend to use a computer system to restore its entire structure and bring the decoding of the brain code to each individual neuron. But is it really possible to create an analogue of the brain? And what will it give to humanity?

“Creating a construct of the brain in an electronic version, or, in other words, what programmers call hardware, “iron,” may be theoretically possible,” comments Alexander Kaplan. — But how can this be done in practice, given that there are 86 billion nerve cells in the human brain, and there are four orders of magnitude more connections between them? Even if these connections are made of the thinnest conductors - calculate how much such a computer brain will weigh and what dimensions it will have. Nothing less than a few high-rise buildings.”

But, the psychophysiologist emphasizes, this is not the main difficulty in building an electronic model of the brain. “What about its informational content? he asks. - What's the point if we release, for example, a new computer, and do not load it software? This electronic monster will be no better than an ordinary stone. It will be necessary to saturate this aggregate with content, fill it with programs, one more complicated than the other, databases and knowledge ... Maybe then it will come to life? Alas, we don't know."

“The real human brain grows, from an infant to an adult, gradually forming a picture of the world for itself, accumulating knowledge, self-programming. Therefore, even if you download the entire Lenin Library or the US Congress Library into the electronic brain, nothing good will come of it. Knowledge will not interact with each other, but will simply lie there, like on library shelves - on demand. Although the brain needs them not in book form, but in operational form - so that at any moment you can remember a specific thing and cross one with another, because each person has his own individual way of operating knowledge, ”emphasizes Professor Kaplan.

“There are almost a million billion connections between nerve cells in the human head, while the most complex modern superprocessor has only two to three billion contacts. Is it possible to reproduce on silicon cells all the richness of the interneuronal connections of the human brain if we do not know the elementary codes of their functioning? And we are unlikely to find out even in the distant future .... So a complete computer copy of the brain, if it is feasible, is only in theory: it is too complicated for our civilization, since we simply do not know the brain circuit, ”the Russian psychophysiologist sums up.

However, a group of neuroscientists led by Professor Theodore Berger of the University of Southern California at Los Angeles recently announced the creation of the world's first prosthetic brain. More precisely, one of its departments - the hippocampus, which is responsible for long-term memory. According to the developers, unlike other similar devices that only stimulate brain activity, their invention will really replace the hippocampus and perform all its functions using an embedded silicon chip.

To what extent does this achievement really bring us closer to prosthetics of the most complex part of the human body?

“These studies have nothing to do with the brain prosthesis,” says Professor Kaplan. - Although the so-called "hippocampal chip" exists, and it was really developed under the guidance of the American researcher Ted Berger. I know him personally and know for certain that Berger's experiments were carried out on rats, in whose hippocampus dozens of very thin conductors were implanted. At the other end, they were combined with the same chip sewn under the skin on the animal's skull. Berger found algorithms for distributed electrical stimulation of the hippocampus through conductors that replaced its natural activity. An implanted chip controlled these algorithms. If the hippocampus suddenly began to work poorly, then turning on the chip improved things. However, we are talking here about just one, very small skill of behavior. There are thousands of such skills. You can't build a chip for every skill. So, unfortunately, there is not even a hint of a whole brain prosthesis here ... ”

Maybe the “brain” chips can be used to replace some elementary impaired functions of the body, Kaplan notes. For example, in the fight against Parkinson's disease, when the entire brain disorder depends on the incorrect functioning of the local and very small structure. “But replacing all the functions of the brain is the same as creating, say, a physical model of the Universe on Earth ...,” the scientist is convinced.

Andrey Volodin

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Your brain, which should be a steel trap for information, turns into a colander over the years. Life goes on as usual, and less and less is deposited in the head. How so? And so - everything needs training. Ordinary, day-to-day repetitive tasks dull the brain, it becomes no need to develop. Don't take the speed of gray (actually brown) matter for granted. A flexible and sharp mind is not a given, but the result of work on oneself. I will tell you what conditions to apply so that the period of normal functioning of your head increases. And if this idea does not seem brilliant to you, then you are already bad at thinking.

Let the brain sweat

Put down the calculator

How?

And read at night

What exactly?

Think about what you eat and drink

Spices

And juices

get distracted

And don't forget to rest

How?

switch

Alcohol renders big influence on human development. It is important to emphasize that the effect is purely negative, without positive changes for the body. drinking man. As you know, all organs of the body suffer from alcohol, but one of the main organs responsible for all the processes of the functioning of the body is especially susceptible to destruction. It is undoubtedly the brain that suffers the most from the effects of alcohol. What is the brain of an alcoholic and what effect does alcohol have on it?

What happens to the brain of a drunk person?

Alcohol has a direct effect on the brain, causing the body to produce more dopamine than a non-drinker. This is also observed in people prone to alcoholism. Dopamine increases the desire of the drinker to consume alcoholic beverages, as a result of which the alcoholic experiences the pleasure of drinking the drink every time.

Dopamine is one of the neurotransmitters that transmit electrical impulses from one neuron to another. In this circuit, dopamine acts as a mediator of pleasure, symbolizing a certain reward system.

Alcohol blocks the activity of dopamine antagonists, that is, substances that block excessive activity of the neurotransmitter. As a result, dopamine carries out an active activity that does not find obstacles in its path.

Studies have shown that people who are at risk or constantly drink alcohol have higher levels of dopamine than non-drinkers. The release of dopamine increases the attraction of alcohol to the drinker, thereby increasing the desire to drink another glass of alcohol.

People who are addicted to alcohol experience a number of changes in the brain.

One of the changes is the weakening of the connection between the brain area and its frontal lobe, leading to disastrous consequences.

The frontal lobe is a key point in the regulation of movements. In addition, it plays a significant role in human decision-making, is responsible for judgments, individuality, speech, that is, for all the qualities inherent in every person and distinguishing him from animals. It is quite clear what a failure in the work of this part will lead to - a person from the highest representative of the planet Earth turns into an ordinary animal.

A number of studies have shown that disruption of communication between the brain area and the frontal lobe leads to the consequences described above. The cerebellum, located in this area, suffers no less, as can be seen from the gait of a drunk person. This is explained by the fact that the cerebellum is a regulator of movement, as a result of exposure to alcohol, the regulatory function weakens, a drunk person loses coordination of movement. In addition, the cerebellar sheath remains impaired even a week after drinking alcohol.

Previous studies have clearly shown that chronic alcohol consumption leads to irreversible changes in the structure, metabolism and functions of the brain.

A study led by Baxter Rogers, a professor at Vanderbilt University in the United States, showed that the relationship in the above areas exists even before drinking and persists after, confirming the theory that the changes are irreversible. Patients who were followed up experienced withdrawal symptoms and strong cravings after a week, which they had to report by tapping their fingers.

But it turned out the following - other parts of the brain were involved in making a decision and performing further actions, and not those that are responsible for such operations in healthy people.

Scientists, examining the brains of patients, found fewer functional connections that should have been between the cerebellum and the frontal lobe. This indicates a strong attenuation of neuronal transmission in the two regions. This discovery showed that the brain of an alcoholic is characterized by signs of the functioning of a damaged brain.

Alcoholics dry out the brain: myth or reality?

Researchers medical college Massachusetts cities claim that frequent drinking in large quantities leads to a decrease in brain volume. They found that any alcoholic drinks, especially strong ones, cause problems in the field of thinking, learning and memory, thereby bringing dementia closer.

The volume of the brain decreases with the age of its owner by about 1.7% every 10 years. With alcohol, this process happens faster. In addition, it was found that the brain of a woman is more susceptible to this influence, as a result of which the brain degrades faster than the brain of a man.

Previously, there was an opinion about some of the positive properties of alcohol in case of its moderate use. Human aging and some diseases, such as senile dementia, lead to a decrease in brain volume. In this case, alcohol seemed to be some way to delay this process. Naturally, we are talking about moderate doses. But recent studies have broken this well-established statement - alcohol in any quantities is harmful both to the body as a whole and to the brain.

It is worth understanding - what is the reason for the so-called drying up and what happens to the brain? The main components of the human brain are neurons that are responsible for the talents and abilities of a person, allowing him to be a person with a strong intellect. When drinking alcohol, neurons die first. In the morning after another gathering, a person is thirsty and suffers from headaches. This is due to the fact that the body, trying to remove harmful decay products, increases pressure and increases fluid flow. As a result, a person receives not only headache, but also a partially destroyed brain. He does not notice it himself.

Stress affects the brain much more than you think! Many may recall absent-mindedness, forgetfulness, anxiety, Bad mood, which often accompany stress, but did you know that it also dries out the brain?

Hormones released during stress affect not only the functions of the brain, but also change its structure.

The stress hormone cortisol causes death and prevents the regeneration of hippocampal cells - the most important part of the brain responsible for learning, memory and emotion regulation. In addition, the hippocampus neutralizes stress reactions in the body after a difficult situation is over - a quality that is indispensable in both work and personal life.

Chronic stress causes dystrophy of the medial prefrontal cortex. This negatively affects decision making, working memory, and behavioral control. Stress also damages stem cells in the prefrontal cortex, which negatively affects complex cognitive behavior and socialization. As a result of all these processes, a person's memory and learning ability decrease, and a tendency to anxiety and depression develops.

But the troubles don't end there! Those same stress hormones increase the size and activity of a part of the brain called the amygdala. Among other things, it is responsible for the formation and storage of memories of various events, accompanied by vivid emotionality. They are stored as long-term memories, and depending on the type of emotion, we avoid or, on the contrary, wait for such events again. Cortisol-induced changes color memories with fear, anxiety, or aggression.

All these violations can affect our relationships with others, the ability to learn and make decisions, and the achievement of long-term goals. In addition, they make it harder to deal with stress in the future, which causes a kind of vicious cycle.

Fortunately, there is an antidote for all of this! You will be surprised, but this is physical exercise. They improve defense mechanisms against stress, as well as increase the size of the brain and improve its cognitive functions.

Physical activity stimulates the release of brain-derived neurotrophic factor, a substance that is responsible for healthy brain regeneration and neutralizes stress. It strengthens neurons and keeps them healthy, as well as stimulates the formation of new nerve cells. The more we exercise, the more the brain-derived neurotrophic factor is released, and the more actively the processes of brain regeneration take place, especially in the hippocampus.

Exercise also enhances the release of growth hormone, somatotropin, which is responsible for the development of cells throughout the body. Somatotropin slows down the aging process and even increases brain volume. Fast running for only 30 seconds increases the content of somatotropin by 6 times, and this effect lasts for 2 hours.

Don't worry, to achieve a positive effect on necessarily spend long hours in the gym. An analysis of a number of studies has shown that 5-minute sports breaks are enough to relieve stress and improve mood. So if you have a free moment, do something that raises your heart rate or engages your muscles. Exercise will help keep the brain and not go crazy!

atrophy of the brain gradual death of brain cells, destruction of the connections of neurons and nerve cells. In this case, disturbances can occur in the cortex or in the subcortex of the human brain.

Often, atrophy of the cerebral cortex occurs in old age, and for the most part such a diagnosis is made to the weaker sex.

Violation can appear in fifty - fifty-five years, and end with dementia.

This is due to the fact that with aging, the volume and weight of the brain becomes smaller.

But in some cases, there is such a process as brain atrophy in newborns. There are a lot of reasons for this disease, but in any case, it is extremely serious and unsafe.

It should be noted that given deviation characteristic of the frontal lobes, which control executive functions. These functions include control, planning, inhibition of behavior, thoughts.

Causes of the disease

One of the main causes of brain atrophy is a hereditary predisposition to this disease. But the violation can also appear in other ways. reasons:

1. The poisonous effect of alcohol, some drugs and medicines. In this case, damage to both the cortex and subcortical formations of the brain can be observed.
2. Injuries, including those obtained during neurosurgical intervention. The damaging effect on the brain tissue appears when the vessels are squeezed and the manifestation of ischemic abnormalities. In addition, this can also appear in the presence of benign formations that compress the blood tract.
3. Ischemic manifestations can also occur due to significant damage to the vessels by atherosclerotic plaques, which is typical for the elderly, which causes a deterioration in the nutrition of the nervous tissue and its death.
4. chronic anemia with a significant decrease in the number of red blood cells or hemoglobin in them. This deviation causes a decrease in the ability of the blood to attach oxygen molecules and carry them to the tissues of the body, and to the nervous ones too. Ischemia and atrophy appear.

However, there is also a list of conditions conducive to such violation:

• low mind loads;
• excessive smoking;
• chronic low blood pressure;
• long-term use of substances that constrict blood vessels.

Types of atrophy

Consider what types of brain atrophy there are:

Degrees of atrophy

The development of the deviation occurs according to such scheme:

1. initial stage or brain atrophy of the 1st degree - there are no clinical signs, but there is a rapid development of the disorder and its transition to the next stage of the disease.
2. Second phase- a rapid deterioration in the patient's communication with others. At the same time, a person becomes conflicted, cannot normally perceive criticism, catch the thread of a conversation.
3. Third stage- the patient gradually loses control over behavior. Unreasonable outbursts of anger or despondency may appear, the behavior becomes outrageous.
4. Fourth stage- loss of awareness of the essence of events, the requirements of others.
5. Final stage- The patient does not understand the ongoing events, and they do not cause any emotions in him.

Depending on the affected areas of the frontal lobe, speech disorders, lethargy, indifference or euphoria, sexual hyperactivity, certain types mania.

The latter moment often makes the patient a danger to society, which is an indication for his placement in a psychiatric hospital.

In case of impaired blood supply to the brain, one of the diagnostic signs may be the death of the temporal muscle, which is observed in some patients.

Symptoms of brain atrophy

The existing symptoms of the lesion can have significant differences, depending on which parts of the organ are destroyed. With cortical atrophy observed:

• decreased ability to think and analyze;
• change in tempo, tone and other features of speech;
• deterioration of memory to the absolute inability to remember anything;
• impaired motor skills of the fingers;
• defeat of the subcortical parts leads to the appearance of more serious symptoms.

Their peculiarity depends on the purpose of the violated parts:

• atrophy of the medulla oblongata - impaired breathing, cardiovascular activity, digestion, protective reflexes;
• damage to the cerebellum - a violation of the tone of the muscles of the skeleton and coordination of a person;
• death of the midbrain - the disappearance of the reaction to external stimuli;
• atrophy of the diencephalon - loss of the ability to thermoregulate, homeostasis, failure in the balance of metabolic processes;
• atrophy of the forebrain - the loss of all types of reflexes.

Significant damage to the subcortical structures often causes the patient to lose the ability to independently maintain life, hospitalization and death in the long term.

This degree of atrophy occurs very rarely, more often after severe injuries or poisoning damage to the brain tissue and large blood vessels.

Therapy for brain atrophy

In the treatment of cerebral atrophy, it is important for a person to provide good care, as well as increased attention from relatives. To alleviate the symptoms of atrophy of the cerebral cortex, only the treatment of manifestations is prescribed.

Upon detection of the first signs of atrophy processes, it is necessary to create a patient calm environment.

He should not change the standard way of life. The best is the performance of ordinary household chores, support and care from loved ones.

It is extremely harmful to keep a patient in a medical institution, because this will only worsen his condition and accelerate the growth of the disease.

For other treatments include:

• the use of a sedative;
• the use of mild tranquilizers;
• taking antidepressants.

These tools help a person to maintain a calm state. The patient certainly needs to create all conditions for active movement, he must regularly engage in simple daily activities.

Among other things, a person with such a disorder should not sleep during the day.

Preventive measures

There are no effective ways to prevent this disease today. You can advise only, in time to treat all existing violations, to lead active life and have a positive attitude.

Vital people often live to a ripe old age, and they do not show any signs of atrophy.

At the same time, it should be understood that over the years, not only brain disorders can occur - other organs are subject to changes. These conditions of the body are related to the development of atherosclerosis of blood vessels, because as a result of this disease, their narrowing occurs.

There are people in whom the development of atherosclerosis occurs much faster, which is the cause of early deterioration of the body. It is in them that bright processes of atrophy are observed.

Warning methods atherosclerosis:

Brain atrophy is a disease that is not treated with modern medicines. This violation does not develop immediately, but eventually ends with dementia.

To preempt negative consequences, preventive measures must be taken. Among other things, if you have any problems, it is very important to consult a doctor in time - this will help maintain good health for many years.

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