A head transplant to a Russian programmer is the end of a sad story. The first head transplant was decided to be done to the Chinese

On July 18, a little over 100 years ago, in 1916, Vladimir Demikhov, a man who stood at the origins of Russian transplantology, was born into a peasant family.

He was the first to make an artificial heart and implanted it in a dog who lived with him for 2 hours. Demikhov was also the first to transplant a separate lung, a heart together with a lung, a liver, and developed the mammary-coronary bypass procedure. One of the areas of his work was attempts at head transplants. Back in 1954, he first implanted a second head in a dog and repeatedly successfully repeated this procedure.

Today, a heart transplant is still one of the most complex operations in the world, but no longer unique. Only in Russia more than 200 such operations are performed annually. Liver transplant is gradually becoming a routine procedure, as well as many other operations developed by Demikhov. Only head transplantation still remains one of the unsolved problems of transplantology - science has advanced to a large extent over the past 60 years, but it still has not reached head transplantation to a living person.

MedAboutMe figured out why it is more difficult to transplant a head than a heart, and what problems, besides medical and physiological ones, confront scientists in this field.

Body or head?

The essence of the head transplant operation is to engraft the head of one living being to the body of another. It can be carried out in two ways:

The head of the "receiving party" is not removed - and Demikhov did just such experiments. In total, he created 20 two-headed dogs. The head is removed from the body, that is, the donor's head should remain the only one on the body.

It is worth noting right away: the question of which of the two organisms is the donor (the one who shares organs), and which is the recipient (the one to whom the organs are transplanted) has not yet been finally resolved:

On the one hand, the body is 80% of the body, and in this perspective, the head is transplanted onto a new body. Both in the media and among a significant part of scientists, they are talking about head transplantation. On the other hand, by default, we consider the head to be a more significant part of the body, because it contains the brain that defines a person as a person. In this perspective, it would be more correct to talk about a body transplant. Medical problems of a head transplant

Scientists talk about three main problems that have not yet been solved with head transplantation.

risk of transplant rejection.

Well, let's say that the achievements of modern medicine will make it possible to cope with this problem, at least for a short time. In the end, even in the late 1950s, after the operation, Demikhov also had dogs with two heads, and even a two-headed monkey for some time - though not for long, well, medicine was developed much worse.

Risk of brain death when the blood supply is cut off.

To keep the neurons of the brain alive, they need an uninterrupted supply of blood that carries oxygen and nutrients and removes harmful waste products from the nerve cells. Disabling the blood supply to the brain, even for a short time, leads to its rapid death. But this problem can be solved with the help of modern technologies. For example, when transplanting a monkey, the head was cooled to 15°C, which made it possible to largely prevent the death of brain neurons.

The problem of connecting parts of the central nervous system of the body and head.

This question is the most difficult and has not yet been resolved. For example, breathing and heartbeat are controlled by the autonomic nervous system and the brainstem. If you remove the head, the heart will stop, breathing will stop. In addition, it is necessary to correctly connect all the processes of neurons coming out of the skull into the spinal cord, because otherwise the brain will not receive information from the body's sensors and will not be able to control movement. But the spinal cord is not only motor activity. This is also tactile sensitivity, proprioception (sensation of one's body in space), etc.

Skeptics also remind that if scientists and doctors learned how to splice a torn spinal cord - and this is what we are talking about in this case, then first of all this technology should be applied to hundreds and thousands of people with already existing spinal cord injuries.

In 2016, an international team of scientists from the US and South Korea proposed using polyethylene glycol (PEG) to splice damaged nerve pathways in the spinal cord. During the experiment, the scientists managed to at least partially restore the cut spinal cord of 5 out of 8 animals: they were alive a month after the start of the experiment and demonstrated the ability to move. The rest of the animals died paralyzed.

Later, scientists at the University of Texas improved the solution for splicing the spinal cord, enhancing its properties with graphene nanoribbons, which should act as a kind of building frame for nerve cells.

There is also evidence that South Korean scientists managed to restore the ability to move rats with a cut spinal cord and achieve good results in a dog whose spinal cord damage was 90%. True, the degree of evidence of these experiments is rather low. Scientists have not provided evidence that the experimental animals really had a damaged spinal cord, and the sample is too small.

In any case, according to experts, after doctors learn how to confidently restore a torn spinal cord, head transplantation will be possible, at best, only in 3-4 years.

Psyche, ethics and the two brains of the body

The above problems are not the only ones. Even the theoretical possibility of a body transplant raises many questions on the verge of ethics, physiology and psychiatry.

Scientists believe that we perceive the world not only "through the head", but also to a large extent through bodily sensations. The role of proprioception in human life is enormous - we cannot realize it, since it is a part of human existence. However, psychiatrists describe rare cases of loss of the sense of proprioception - it is difficult for such people to exist in this world.

Another important point. The brain is the largest collection of nerve cells in the human body. But there is another extensive nervous network - the enteric nervous system (ENS), located in the walls of the gastrointestinal tract. It is sometimes called the "second brain" because it can "make decisions" without the participation of the brain, while using the same neurotransmitters as the latter. Moreover, 95% of serotonin (the “mood hormone”) is produced not “in the head”, but precisely “in the intestines”, and it is this hormone that largely determines our understanding of the world.

Finally, in recent years there is growing evidence that the gut microbiome also has an impact on the formation of human personality.

All these facts cause scientists to doubt that it is the head that determines the personality of a person. It is quite possible that the bodily part of the personality will have such an influence on the transplanted head that the question will still arise: who is the master in the body? And how the human psyche will transfer this new view of the world is not yet known.

Russian head transplant

For the past couple of years, the media has periodically flashed information about the decision of a resident of Russia, a programmer Vitaly Spiridonov, to become a "guinea pig" and take part in the world's first head transplant operation on a living person. Spiridonov suffers from an incurable disease - Werdnig-Hoffman disease, congenital spinal amyotrophy. His muscles and skeleton atrophy, which threatens him with death. He gave his consent to Sergio Canavero to participate in the operation, but the procedure is delayed.

Chronicle of a head transplant 1908. French surgeon Alexis Carrel developed techniques for connecting blood vessels during transplantation. He transplanted a second head to the dog and even recorded the restoration of some reflexes, but the animal died after a few hours. 1954 Soviet surgeon Vladimir Demikhov, also as part of the development of a coronary bypass procedure, performed a transplantation of the upper body - the head with front legs - on a dog. The grafted body parts could move. The maximum life expectancy in one case was 29 days, after which the animal died due to tissue rejection. 1970 The American neurosurgeon Robert J. White cut off the head of one monkey and connected the body's blood vessels to the head of another animal. He also did not touch the nervous system. At the same time, White used deep hypothermia (cooling) to protect the brain at the stage of its temporary disconnection from the blood supply. The grafted head could chew, swallow, and move its eyes. All the monkeys involved in these experiments died within a maximum of three days after surgery from the side effects of high doses of immunosuppressants. year 2012. After several experiments on head transplantation by other scientists, the experiments of the Chinese transplantologist Xiaoping Ren gained fame. He successfully transplanted the head of one mouse onto the body of another - at best, the experimental animals lived for six months. year 2013. Italian transplantologist Sergio Canavero made a statement about the possibility of human head transplantation. 2016 Canavero and Ren reported successful head transplants in mice, rats, dogs, and monkeys, and equally successful reconnection of cut animal spinal cords using fusogen proteins. True, the scientific community doubts the reliability of the published results, since only photos of dubious quality were presented instead of videos. Yes, and Ren and Canavero themselves admitted that we are talking about restoring only 10-15% of the nerve connections in the spinal cord, at best. According to scientists, this should be enough for at least some small movements. 2017 Xiaoping Ren reported a successful head transplant on a human corpse. True, it turned out to be quite difficult to prove success, because it is not clear whether it is possible to restore the nerve connections of the spinal cord in this way. Bright future. Sergio Canavero (Italy) and Xiaoping Rei promise to transplant the head of a living person in the coming years. They hope to become Vitaly Spiridonov. But it seems that the first "experimental" will be a citizen of China - it is more beneficial for business. Conclusions Transplantology is developing by leaps and bounds. The annual number of kidney transplants in the world is measured in tens of thousands, liver and pancreas - in the thousands. Surgeons have learned how to transplant limbs and faces, a woman with a transplanted uterus recently gave birth, and in 2014 a penis was successfully transplanted. Sooner or later, humanity will cope with a head (or body) transplant. But for now, we can say for sure: a living person, assembled from the body and head of different people, we will not see soon. Today, medicine is clearly not yet ready for this. Take the testTest: you and your health Take the test and find out how valuable your health is to you.

Shutterstock photo materials used

The science that studies organ transplantation is called transplantology. Until a few decades ago, the movement of tissues from one organism to another was considered something incredible. In modern surgical practice, transplantation of internal organs is widespread. To a greater extent, this is practiced in developed countries with a high level of medical provision. Transplantation of the liver, kidneys, heart is successfully carried out. In recent years, doctors have begun to perform limb transplants. Despite the high professionalism of surgeons, some operations end in failure. After all, the body does not always "accept" other people's organs. In some cases, tissue rejection is possible. Despite this, a well-known practicing surgeon from Italy decided to take an incredible risk. The doctor is planning a head transplant operation. To many, this idea seems incredible and doomed to failure. However, surgeon Sergio Canavero is confident that head transplantation will be a huge breakthrough in medicine. To date, studies have been carried out and attempts have been made to implement this manipulation on laboratory animals.

Head transplant operation: description

In 2013, an Italian surgeon made a sensational announcement to the world. He planned an operation to transplant the head of a living person onto the body of a corpse. This procedure has interested people suffering from serious diseases that cause immobilization. Surgeon Sergio Canavero has already contacted the intended head donor. It turned out to be a young man from Russia. The patient was diagnosed with a severe pathology of the nervous system - congenital spinal muscle atrophy. At the moment, Valery Spiridonov is 30 years old. Despite quality care, his condition is rapidly deteriorating. The only functioning part of the patient's body is the head. Valery Spiridonov is aware of all the risks of the planned event, but he agrees to go for it. The first human head transplant is expected to take place in 2017.

Sergio Canavero suggests that the transplant will take about 36 hours. To carry out all stages of the operation, more than 100 qualified surgeons will be needed. During the transplant, doctors will change several times. A head transplant is a very complex surgical procedure. To implement it successfully, you will need to connect many vessels, nerve fibers, bones and soft tissues of the neck. The most difficult stage of the operation will be the fastening of the spinal cord. For this purpose, a special adhesive based on polyethylene glycol was made. Thanks to this substance, the growth of neurons is carried out. Each of the stages of the operation is considered risky and can be fatal. However, this does not frighten the patient Valery Spiridonov. The doctor who conceived the sensational operation is also optimistic. Canavero is almost sure of a favorable outcome of the procedure.

Ethical aspects of head transplantation

Such a topic as a human head transplant causes stormy emotions and controversy not only among doctors. In addition to the difficulties in performing transplantation and the risks to the life of the patient, there is another side to the coin. So, many people consider the conceived procedure unacceptable from a religious and ethical point of view. Indeed, it is difficult to realize that the head of a living person will be separated from the body and attached to the neck of a dead person. Nevertheless, people suffering from severe progressive pathologies do not have to think about ethics. For many patients, a head transplant will be an incredible miracle. After all, people doomed to disability will have a new body. Due to the fact that the operation has not yet been carried out, and its outcome is unknown, the public has a conflicting attitude to this issue.

Research

The first research in the field of head transplantation was the experience of the scientist Charles Guthrie. It was held in 1908. The experiment consisted of transplanting a second head onto the dog's neck. The animal did not live long, but it was possible to note a slight reflex activity of the transplanted body part.

In the 1950s, the Russian scientist Vladimir Demikhov managed to achieve better results. Although his laboratory animals also did not last long after transplantation, the transplanted heads were fully functional. Demikhov significantly reduced the time of hypoxia of separated tissues. Similar operations on dogs were later carried out by Chinese scientists. In the 1970s, White transplanted a monkey's head. At the same time, the animal's sense organs functioned.

In 2002, experiments were carried out on laboratory rats in Japan. As for the planned intervention, polyethylene glycol was used. The dissected tissues were refrigerated to prevent cell death. In addition, Sergio Canavero stated that in his latest research involving monkeys, a head transplant was recently performed. She ended happily. The scientist regards a positive result as a signal to conduct an experiment on a person. If the public and the scientific community approve this project, soon people will know about its results.

Human head transplant: scientists' opinion

Despite the positive attitude of the Italian surgeon, scientists and doctors do not share his enthusiasm. Most of them do not believe in the success of the venture. In addition, many doctors believe that a head transplant is ethically unacceptable. The pessimism of colleagues does not affect the decision of the scientist. Canavero recently announced that the transplant will take place with the consent of the members of the state board.

What diseases require surgery

At the moment, it is too early to say whether such an operation will be performed in practice in the future. However, with a favorable outcome, the scientist will experience incredible success. If head transplantation becomes possible, many patients will have healthy bodies. Among the indications for transplantation are:

Tetraplegia developed against the background of cerebrovascular accident.
Muscular spinal atrophy.
Spinal cord injury at the level of the cervical vertebrae.

Difficulties of surgery

A head transplant is a technically complex procedure. In the course of its implementation, doctors may encounter many difficulties. Among them:

Tissue death during head removal. To prevent this, scientists intend to cool the head to 15 degrees. At the same time, neurons must maintain their viability.
Risk of rejection of the transplanted body part.
Prolonged connection of the spinal cord after surgery. In order for the nervous tissue to be properly aligned, the patient is scheduled to be put into a coma for 1 month.

Possible outcomes of head transplant surgery

Given that such operations have not been performed on people before, it is impossible to predict the outcome of this procedure. Even if all the manipulations are performed correctly, it is not known how this experiment can end. Scientists do not exclude the possibility that the spinal cord will be damaged, and the patient will not be able to move. However, even in this case, the operation will be an incredible breakthrough in transplantation.

head transplant cost

How much does a head transplant cost and when will it be put into practice? It is not yet possible to answer these questions. However, some information is available. Thus, an assessment of the equipment and necessary materials for the planned transplant showed that the cost would be about $11 million. In addition, in case of a favorable outcome, a long rehabilitation will be required. According to the Italian scientist, the patient will be able to move independently a year after the operation.

Recently, news broke in the media that Sergio Canavero from Italy and his colleague Xiaoping Ren from China are planning to transplant a human head from a living person onto a donor corpse. Two surgeons have challenged modern medicine and are trying to make new discoveries. It is believed that the head donor will be someone with a degenerative disease whose body is depleted while the mind remains active. The body donor is likely to be someone who died from a severe head injury but whose body remained unharmed.

Human head transplant in 2017 was announced by Italian neurosurgeon Sergio Canavero

First human head transplant

The researchers claim to have perfected the technique on mice, a dog, a monkey and, more recently, a human corpse. The first human head transplant was scheduled to take place in 2017 in Europe. However, Canavero moved the operation to China because no American or European institution allowed such a transplant. This issue is very tightly regulated by Western bioethicists. It is believed that Chinese President Xi Jinping wanted to return China to greatness by providing a home for such cutting-edge work.

In a telephone interview with USA TODAY, Canavero denounced the US or European reluctance to carry out the operation. "No American medical institute or center is pursuing this, and the US government doesn't want to support me," he said.

The human head transplant experiment was met with considerable skepticism, to say the least. Critics cite the lack of adequate prior and animal studies, the lack of published literature on the techniques and their results, unexplored ethical issues, and the circus atmosphere encouraged by Canavero. Many also worry about the origin of the donor body. The question has been raised more than once that China is using the organs of executed prisoners for transplantation.

Some bioethicists argue that it is necessary to simply ignore this topic in order not to contribute to the "circus of the world." However, one cannot simply deny reality. Canavero and Ren may not succeed in attempting a live human head transplant, but they certainly won't be the last to attempt a head transplant. For this reason, it is very important to consider the ethical implications of such an attempt beforehand.

Canavero presents the human head transplant as the natural next step in the transplant success story. Indeed, this story would be just wonderful: people live for many years with donated lungs, livers, hearts, kidneys and other internal organs.

2017 marked the anniversary of the oldest living, handed down by a father to his daughter; both are alive and well 50 years later. More recently, we have seen successfully transplanted arms, legs, and another. The first fully successful one occurred in 2014, as did the first live birth from a woman with a womb transplant.

Certainly face and penis transplants are difficult (many still fail), head and body transplants represent a whole new level of complexity.

Head transplant history

The issue of head transplantation was first raised in the early 1900s. However, transplant surgery at that time faced many challenges. The problem faced by vascular surgeons was that it was impossible to cut and then connect the damaged vessel and subsequently restore blood flow without interrupting blood circulation.

In 1908, Carrel and an American physiologist, Dr. Charles Guthrie, performed the first dog head transplant. They attached one dog's head to the neck of another dog, connecting the arteries so that blood would flow first to the decapitated head and then to the head of the recipient. The severed head was without blood flow for approximately 20 minutes, and while the dog demonstrated auditory, visual, skin reflexes, and reflex movements in the early postoperative period, it only worsened and was euthanized a few hours later.

Although their work on head transplantation was not particularly successful, Carrel and Guthrie made significant contributions to the understanding of the field of vascular anastomosis transplantation. In 1912 they were awarded the Nobel Prize in Physiology or Medicine for their work.

Another milestone in the history of head transplantation was achieved in the 1950s thanks to the work of the Soviet scientist and surgeon Dr. Vladimir Demikhov. Like his predecessors, Carrel and Guthrie, Demikhov made notable contributions to the field of transplant surgery, especially thoracic surgery. He improved on the methods available at the time to maintain vascular nutrition during organ transplantation and was able to perform the first successful coronary bypass operation in dogs in 1953. Four dogs survived for more than 2 years after the operation.

In 1954, Demikhov also attempted to transplant the heads of dogs. Demikhov's dogs demonstrated more functionality than Guthrie's and Carrel's dogs and were able to move, see and lap water. Demikhov's step-by-step documentation of the protocol, published in 1959, shows how his team carefully preserved the blood supply to the donor dog's lungs and heart.

Two-headed dog from Demikhov's experiment

Demikhov showed that dogs can live after such an operation. However, most dogs lived only a few days. The maximum survival of 29 days was achieved, which is more than in the experiment of Guthrie and Carrel. This survival was due to the immune response of the recipient to the donor. At this time, effective immunosuppressive drugs were not used, which could change the results of the studies.

In 1965, the American neurosurgeon Robert White also attempted a head transplant. His goal was to perform a brain transplant on an isolated body, contrary to Guthrie and Demikhov, who transplanted the entire upper body of the dog, not just the isolated brain. This required him to develop various perfusion techniques.

Maintaining blood flow to the isolated brain was Robert White's biggest challenge. He created vascular loops to preserve the anastomoses between the internal maxillary and internal carotid arteries of the donor dog. This system was called "autoperfusion" because it allowed the brain to be perfused by its own carotid system even after it had been torn at the second cervical vertebral body. The brain was then placed between the jugular vein and carotid artery of the recipient. Using these perfusion techniques, White was able to successfully transplant six brains into the cervical vasculature of six large recipient dogs. The dogs survived between 6 and 2 days.

With continuous electroencephalogram (EEG) monitoring, White monitored the viability of the transplanted brain tissue and compared the brain activity of the transplant with that of the recipient. Moreover, using an implantable recording module, it also monitored the metabolic state of the brain by measuring oxygen and glucose consumption and demonstrated that the transplanted brains were in a highly efficient metabolic state after the operation, another indication of the functional success of the transplant.

Head transplant for Russian programmer Valery Spiridonov

Back in 2015, Italian surgeon Sergio Canavero proposed the first live human head transplant as early as 2017. To prove that the procedure would be possible, he reconstructed a severed dog's spinal cord and attached a mouse's head to a rat's body. He even managed to find a volunteer in the person of Valery Spiridonov, but it seems that the operation may not move forward as originally planned.

Doctors from all over the world say that the operation is doomed to failure, and even if Spiridonov survives, he will not live a happy life.

Dr. Hunt Butger, president of the American Association of Neurological Surgeons, said: “I wouldn't wish this on anyone.

Valery Spiridonov volunteered to undergo the world's first full head transplant, to be performed by the Italian neurosurgeon Sergio Canavero, but after a while he changed his mind. Spiridonov suffered from severe muscular atrophy and was a wheelchair user all his life.

Valery Spiridonov, a Russian man in his 30s, volunteered to undergo this surgical procedure because he believes the head transplant would improve his quality of life. Valery was diagnosed with a rare genetic disease called Werdnig-Hoffman disease. This genetic disease causes his muscles to break down and kills nerve cells in his spinal cord and brain. There is currently no known cure.

How did the story of a head transplant to a Russian programmer end?

Recently, Valery announced that he would not undergo the procedure, because the doctor could not promise him what he so wanted: that he would walk again, be able to have a normal life. Moreover, Sergio Canavero said that the volunteer may not survive the operation.

Given that I cannot rely on my Italian colleague, I must take my health into my own hands. Luckily, there is a fairly well proven operation for cases like mine where a steel implant is used to keep the spine straight. Valery Spiridonov said

The Russian volunteer will now seek alternative spinal surgery to improve her life, instead of undergoing an experimental procedure that has been criticized by several researchers in the scientific community.

At the beginning of 2018, foreign media regularly and very actively posted news about the Russian volunteer Valery Spiridonov. However, after the refusal of the operation, their interest in the disabled person subsided.

Human head transplantation is a very complex procedure, as it requires reconnection of the spine. After the operation, it is necessary to manage the immune system to prevent rejection of the head from the donor body.

Some interesting facts:

Spiridonov has already won. The doctors told him that he should have died from an illness years ago.
Valery works from home in Vladimir, about 180 kilometers east of Moscow, running an educational software business.
Spiridonov is terminally ill. He is wheelchair bound due to Werdnig-Hoffmann disease. A genetic disorder that causes motor neurons to die. The disease has limited his movements to feed himself, he controls the joystick on a wheelchair.
Spiridonov is not the only person who volunteered to be the first potentially successful head transplant patient. Nearly a dozen others, including a man whose body is full of tumors, asked doctors to go first.
Spiridonov came up with a new way to help finance the operation, with preliminary estimates that the cost of the operation was between US$10 million and US$100 million. He began selling hats, T-shirts, mugs, and iPhone cases, all featuring a head on a new body.

Head transplant in China

In December 2017, Italian neurosurgeon Sergio Canavero performed the first head transplant on two cadaveric donors in China. With this procedure, he attempted to make spinal fusion (taking an entire human head and attaching it to a donor body) a reality and declared that the operation was successful.

Many scientists around the world believe that the successful human head transplant claimed by Canavero is actually a failure! This is argued by the fact that no actual results of a human head transplant after transplantation have been shown to the public. Sergio Canavero gained a reputation in wide circles as a fraudster and populist.

Dr. Canavero did a head transplant with another doctor named Xiaoping Ren of Harbin Medical University, a Chinese neurosurgeon who successfully grafted a head onto a monkey body last year. Canavero and Dr. Ren were not the only ones involved in this operation. More than 100 doctors and nurses were on standby during this procedure for 18 hours. Answering the question of journalists “how much does a head transplant cost”, Canavero said that this procedure cost more than 100 million US dollars.

The first head transplant in China was successful. Operation on human corpses completed. We did a head transplant, no matter what anyone says! Canavero said at a conference in Vienna. He said that an 18-hour operation on two corpses showed that it was possible to restore the spinal cord and blood vessels.

Sergio Canavero and Xiaoping Ren

Since then, Canavero has been called the "Dr. Frankenstein of medicine" and has been criticized for his actions. We can say that Sergio Canavero is a man who plays god or wants to cheat death.

Ren and Canavero hope their invention could one day help patients with paralysis and spinal cord injuries walk again.

These patients currently do not have good strategies and their mortality is very high. So I try to promote this technique to help these patients,” Prof. Ren told CNBC. “This is my main strategy for the future.”

If doctors really did a head transplant to a person (a living recipient), it would be a breakthrough in the field of transplantology. Such a successful operation could mean saving terminally ill patients, as well as enabling people with spinal injuries to walk again.

Jan Schnapp, professor of neuroscience at the University of Oxford, said: “Despite Professor Canavero’s enthusiasm, I cannot imagine that ethics committees at any reputable research or clinical institution will give the green light to live human head transplants in the foreseeable future… Indeed, attempting such an act , given the current state of the art, would be nothing short of a crime.

Any innovative procedure is sure to face objections and skepticism, and requires a leap of faith. Although it all seems impossible, a human head transplant would revolutionize the field of medicine if successful.

Ethical Issues

Some doctors say the chances of success are so low that attempting a head transplant would be tantamount to murder. But even if it were feasible, even if we could connect the head and body and have a living person at the end, this is only the beginning of the ethical questions about the procedure for creating a hybrid life.

If we transplanted your head onto my body, who would it be? In the West, we tend to think that what you are - your thoughts, memories, emotions - is entirely in your brain. Since the resulting hybrid has its own brain, we take it as an axiom that this person will be you.

But there are many reasons to worry that such a conclusion is premature.

First, our brain is constantly monitoring, reacting and adapting to our body. An entirely new body would cause the brain to engage in a massive reorientation to all of its new inputs, which could over time change the fundamental nature and connectivity of the brain (what scientists call a "connect").

Dr. Sergio Canavero stated at a conference in Vienna that the head transplant on a cadaver was successful.

The brain will not be the same as it was before, still attached to the body. We don't know exactly how it will change you, your sense of self, your memories, your connection to the world - we only know that it will.

Second, neither scientists nor philosophers have a clear idea of how the body contributes to our essential sense of self.

The second largest nerve cluster in our body, after the brain, is the bundle in our gut (technically called the enteric nervous system). The ENS is often described as a "second brain" and is so vast that it can operate independently of our brain; that is, it can make its own “decisions” without the involvement of the brain. In fact, the enteric nervous system uses the same neurotransmitters as the brain.

You may have heard of serotonin, which may play a role in regulating our moods. Well, about 95 percent of the body's serotonin is produced in the gut, not the brain! We know that the ENS has a strong influence on our emotional states, but we do not understand its full role in determining who we are, how we feel, and how we behave.

Moreover, there has recently been an explosion in research into the human microbiome, the large mix of bacterial life that lives within us; It turns out that we have more microorganisms in our body than in human cells. More than 500 types of bacteria live in the gut, and their exact composition differs from person to person.

There are other reasons to be concerned about a head transplant. The United States suffers from an acute shortage of donor organs. The average waiting time for a kidney transplant is five years, a liver transplant is 11 months, and a pancreas is two years. One corpse can give two kidneys, as well as a heart, liver, pancreas, and possibly other organs. Using the whole body for a single head transplant with a slim chance of success is unethical.

Canavero estimates that the cost of the world's first human head transplant is $100 million. How much good can be done with such funds? Calculating is actually not so difficult!

When and if it becomes possible to repair a severed spinal cord, this revolutionary achievement should be aimed primarily at the many thousands of people who suffer from paralysis as a result of a torn or injured spinal cord.

There are also unresolved legal issues. Who is a hybrid person legally? Is the "head" or the "body" the legitimate person? The body is more than 80 percent of the mass, so it is more of a donor than a recipient. Who according to the law will be the children and spouses of the donor to the recipient? After all, the body of their relative will live, but with a “different head”.

The history of head transplantation does not end there, on the contrary, every day new facts, questions, problems emerge.

Like snow on the head fell on Wednesday the message that the Italian neurosurgeon has chosen a man who will be the first in the world to transplant someone else's body. The doctor's choice fell on a Russian, 30-year-old Valery, a programmer from Vladimir, who suffers from severe muscular atrophy, which has forever chained him to a wheelchair.

According to the computer scientist, he decided to take a desperate step, because he wants to use the chance to get a new body before his death. “Am I afraid? Of course I'm afraid. But it’s not so much scary as very interesting,” Spiridonov said in an interview, “However, you need to understand that I don’t have many options. If I miss this chance, my fate will be unenviable. Every new year worsens my condition. It is known that while the doctor and his future patient had not yet met, Canavero did not study Spiridonov's medical history and they only communicated via Skype.

According to the surgeon, he receives many letters asking for a body transplant, but his first patients should be people suffering from muscle atrophy.

It is reported that the 36-hour operation will cost more than $11 million, the donor body is planned to be taken from a healthy person who has died of a brain. The success of the operation should ensure the simultaneous separation of the heads from the body of Spiridonov and the donor, while it is assumed that after the operation Spiridonov will be put into a state of coma for four weeks so that the neck muscles do not move, then he will be given abundant immunosuppressants to prevent tissue rejection.

Spiridonov was diagnosed with a rare genetic disease - Werdnig-Hoffman disease, which progresses every day. This is a severe form of muscle atrophy in which degenerative changes occur in the neurons of the spinal cord. Children with this diagnosis usually die, often in people the respiratory and facial muscles are affected. “Now I can barely control my body. I need help every day, every minute. Now I'm 30, but people with this disease rarely live past 20,” he says. According to the doctor, the donor body can be taken from a person who has been in a car accident or sentenced to death.

It is reported that the operation can take place as early as 2016.

Details are planned to be revealed at an upcoming conference of neurosurgeons in Annapolis this summer, in which the doctor and his future patient are going to participate.

This is not the first time that Canavero plans to transplant someone else's body to a person. Two years ago, Gazeta.Ru, as a surgeon, intends to carry out this operation. Canavero claimed that experiments with rats carried out by his group made it possible to rewire the spinal cord to another head. In order for the “new” head to work, surgeons need to be able to “solder” the cut axons. These are long processes of neurons, they are also wires with which neurons communicate with each other, transmit information between nerve cells, as well as signals to muscles and glands.

The doctor claims that clipped axons can be repaired using molecules such as polyethylene glycol, widely used in pharmaceuticals, or chitosan, a biopolymer isolated from crustacean shells.

The main role in the operation is given to the "ultra-sharp scalpel", which will cut off the spinal cord. Canavero calls this moment the key moment in the whole operation, the axons will inevitably be damaged in its course, but they must be given the opportunity to recover.

Canavero reasserted himself in February of this year, hinting that the world's first full-body transplant could take place in 2017, with all the technical hurdles along the way already surmountable. In his latest article published in the journal Surgical Neurology International(for some reason the link has ceased to be active), the doctor listed the latest achievements that should help in the revolutionary operation.

This is the cooling of the bodies of the donor and recipient, the dissection of the tissues of the neck and the connection of large blood vessels with small tubes before the spinal cord is dissected.

Canavero suggests that in the event of a successful outcome of the operation, the patient will be able to move, speak in the same voice and feel his own face. And physiotherapy will get him back on his feet in a year.

Despite all these successes, the plans of the Italian professor have many critics among the scientific community. “There is no evidence that connecting the spinal cord and brain will lead to the restoration of motor function after a head transplant,” said Richard Borgens, director of the Paralysis Center at Purdue University (USA). New York University medical ethicist Arthur Kaplan called Canavero crazy.

“I don’t think it’s possible,” says Dr. Eduardo Rodriguez, a professor who in 2012 performed the first full face transplant.

According to him, even today, after decades of studying spinal cord injuries, there are very few ways to restore motor function in injured people.

The first experiments on head transplantation were carried out back in 1954 by a Soviet surgeon who successfully transplanted second heads to several dogs. The head transplant operation was performed in the USA on a monkey back in 1970 by neurosurgeon Robert Joseph White. At that time, there were no methods that could qualitatively connect the spinal cord with the brain, so the monkey was paralyzed and died eight days later. Experiments on head transplantation in mice have recently been carried out in China.