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According to the British "Daily Mail" reported on November 17, Italian neuroscientist Sergio Canavero (Sergio Canavero) held a press conference in the Austrian capital of Vienna on the same day, announcing that the world's first human head transplantation has been successfully carried out by him on a set of remains, and the location of the implementation of the operation is precisely in China.

Canavero said that after a surgery that lasted about 18 hours, he and a team from China's Harbin Medical University succeeded in connecting the head of one cadaver to the spine, blood vessels and nerves of another. Prof. Ren Xiaoping from China was involved in guiding the operation.

Ren Xiaoping and Canaveral

Canavero said he would release the full report of the experiment, including the surgical procedure and the timeline for performing the transplant, within days to provide enough evidence that the surgery was genuine and reliable.

What everyone thought was impossible is now happening, Canavero said.

Two years ago, Canavero announced that he was ready to perform the first head-replacement surgery on Spyridonov, a Russian with spinal muscular atrophy.

However, because the controversial surgery is not supported by scientific institutions in Europe and the United States, as well as by the American authorities. Spiridonov is still undergoing traditional treatment methods.

About a year ago, Canavero and his team say they completed head-swapping experiments on puppies. The results of the experiment showed that a dog's spinal cord could be reconnected after it was severed, and the dog was able to walk and wag its tail again after a broken neck and three weeks of paralysis.

Domestically, Professor Ren Xiaoping of Harbin Medical University and his research team have been studying "head and body reconstruction" (the professional term for head transplantation) in the laboratory through animal experiments for about three years.

"In terms of research, some foreign professors are working with us, Dr. Canavero from Italy being one of them."

As a preview of this major surgery, Canavero had previously succeeded in transplanting the heads of rats and monkeys with Ren Xiaoping's team. In May of this year, they successfully transplanted the head of a mouse to the back of a rat, with the former surviving for an average of 36 hours.

Now, after the success of the head-swap, Canavero said that experiments on living people are "imminent" and that the next step will be to prepare for the head-swap between two brain-dead people, and the final step will be the head-swap of a living person.

As envisioned by this neurosurgeon, the head-swapping procedure looks like this:

In the first step, the head and body for transplantation will be cooled to about 12 degrees Celsius to 15 degrees Celsius to slow down the rate of cell death.

In the second step, the patient's and donor's necks will be severed at the same time, with the large blood vessels connected by artificial vessels. Next, the cervical spine is severed.

The patient's head is then quickly transplanted into the donor's neck, and a medical "glue" is used to join the spines together, sewing the muscles and blood vessels of the two together.

Weak electrical currents are also used to stimulate the nerves within the cervical spine during the patient's 4 weeks of healing to strengthen the connection between the head and the body.

Once the surgery is successful, the patient will learn to walk within a year with the help of physical therapy and learn to adapt to his new body, including feeling his face and even speaking in his original voice, Canavero said.

If the head-swapping operation is successful, will the person be able to "live forever"?

Canavero said this is a scientific exploration in the medical field, not a commitment to prolonging life.

Ren Xiaoping also pointed out that there is currently no cure for stubborn diseases such as cancer recurrence, congenital spinal muscular dystrophy and paraplegia. In the future, based on breakthroughs in some key technologies, transplanting the bodies of physically healthy but brain-dead people for those who suffer from these diseases but have a healthy brain is a potential treatment option.

"If indeed in the future a successful human living head transplant can be performed, this will change everything." Canavero said in the release.

However, "head transplantation" is still a big problem. Not only is it clinically and technically immature, but it is also impossible to reach a social consensus at the legal and ethical levels.

New Scientist magazine has commented that, regardless of whether the head is likely to survive the "disembowelment", "head transplants" are bound to attract a great deal of moral controversy. For example, if the patient recovers and has a child, to whom does the child belong? In addition, a brand new body may also bring huge psychological pressure to the patient. ......

Ren Xiaoping also pointed out that the above idea needs more experiments to realize, and more resources and policies to support it. The current focus of the team is to try to solve some technical and challenging scientific and ethical issues first, and if there is a major breakthrough in scientific research one day in the future, or if clinical research is needed, then human beings may be involved. Even if we have to do it, our country certainly has competent authorities and corresponding regulations to regulate such a large project, and it is never up to a certain doctor or researcher to decide where to do it and to whom to do it.

There is always a sense of witnessing history, but whether this development is good or bad remains for mankind to continue to explore and study.

"Head-swapping surgery successful, Chinese doctors appear for media interviews". The media got excited, the title seemed to make the humble Chinese medical science and technology raise its eyebrows, but on closer inspection, it was a successful head-swapping operation on a human cadaver. So far, there are no specific details of this "successful technology", whether it is to swap the head and torso of the two cadavers, sewing, or to connect the spinal nerves of the two cadavers and realize normal physiological functions with the support of medical equipment. It is believed to be at least the latter, the former being too pedestrian. Because of the complexity of the central nervous system, there has been no medical breakthrough so far in repairing damage to spinal nerves.
Let's talk about the future of this technology, whether it is the standard for "living head transplantation", and if so, it is the pinnacle of transplantation medicine, "brain transplantation". Putting aside the ethical issues for the moment, the conditions for successful head transplantation are a brain-dead patient with normal circulation of body organs and a patient with necrotic body organs and an active brain (paraplegic), and is it not the case that fewer people can fulfill these two conditions at the same time?

Even if a living brain transplant is medically successful, will the brain in the new body have the same memory functions as the original (and if not, will it have to start learning from kindergarten)? Will the new brain be able to mobilize and command the new body? Will the new brain and the new body fight (immune rejection)? And so on. There are so many difficult questions ......

From the looks of it, Canavito and the Chinese doctors are at best a cadaveric neural connection experiment, and the reports of great success with the head-swapping technology are mere gimmicks. Then again, ethically speaking, who has the right to decide whose body to transplant when this technology is actually successfully realized one day? Whose head to go? Whose body to take? Who can guarantee that this technology will only be used for medical purposes for brain-dead patients and paraplegics? Will the powerful and the rich be able to achieve the ageless goal of "long live"? The ancient feudal rulers, who tried unsuccessfully to make elixirs for the sake of immortality and sacrificed their lives, may be successfully realized in the future.

Terminally ill, in a serious car accident, dying of old age ...... want to live, what to do? Nothing, just give the head a new body. This kind of previous only in science fiction and movies in the bridge, recently seems to have come true signs. Not long ago, Italian and Chinese medical scientists jointly announced that the first cadaveric head-swapping surgery in humans was declared a success. What's going on? Is it really possible to "change heads"? Let's take a look at it together with our homepage.

With the advancement of modern medicine, organ transplantation is nothing new, and every year, many patients are given a new lease of life by replacing their kidneys or hearts with new ones. Head transplants, however, have long been seen as something that could only happen in science fiction and mythology.

1969 American horror sci-fi movie Frankenstein Must Be Destroyed

And just recently, things seem to have taken a turn for the worse.

On November 17th, Italian medical doctor Sergio Cannavaro announced that the world's first head transplant was declared a success in China.

What the hell is going on?

Dr. Cannavaro is an Italian neurosurgeon. In Western medicine, he is known as "Dr. Crazy" because of his fervent advocacy of "head transplantation".

As early as 2013, Cannavaro boasted at an academic conference that he wanted to be a pioneer in human head transplantation; two years later, in 2015, a 30-year-old computer engineer from Russia volunteered to be a volunteer in Cannavaro's experiment. The engineer, who was born with spinal muscular atrophy, had been paralyzed since he was a child and his condition had worsened over time. In his words, "I had no choice but to get a new body".

In July of that year, Cannavaro met another person of the same ilk - Prof. Ren Xiaoping from Harbin Medical University. Prof. Ren was one of the country's leading surgical experts, and had previously gained national and international attention for his initial successful experiments on mice with head-swapping. With a candidate and partner in place, Cannavaro was confident. It was then that he announced that by December 2017 at the latest, he would perform his first surgery.

At a conference in Vienna, Austria, on the 17th of this month, Cannavaro responded to his promise: the first human head transplant was successful on a cadaver. Led by Prof. Xiaoping Ren, the doctors finally succeeded in transplanting the head from one cadaver to another after 18 hours of surgery. "After a lot of hard work by a lot of people, finally, a historic moment happened in China." Cannavaro said.

Prof. Ren Xiaoping also said in the interview that the results of this surgery have been published in relevant academic journals. He and Carnavaro will reveal more details and results next week. After the success of this trial, the pair's next goal is to perform head transplants on brain-dead patients, also known as vegetative patients. Ultimately, head replacement surgery for living people will be realized.

Replacing one's own organs has long been a dream of human beings. In Liao Zhai Zhi Yi (Liao Zhai Zhi Yi) written by Pu Songling in the Qing Dynasty, there is a mythological story about a scholar who had his heart replaced by a magistrate and then went on to become a high school graduate. In modern times, with the in-depth study of the human body and the development of modern medical technology, human organ transplantation began to become possible. In 1954, the first liver transplant was declared a success in the United States, and the volunteers were a pair of twins.

In 1981, Stanford University School of Medicine performed the first successful heart and lung transplants. Since then, organ transplantation has become a mainstream medical practice, and the number of organs that can be transplanted has grown. 2013 saw a woman in Sweden undergo a successful uterus transplant and give birth to a baby the year after the operation. It's natural to wonder if the brain can also be transplanted. In fact, scientists have been experimenting with this for a long time. In 1954, Soviet surgeon Vladimir Demikhov grafted the front half of a small dog's body onto that of a large dog, and tried several times. Although these "two-headed dogs" miraculously survived, none of them lasted more than six days.

In 1970, Dr. Robert White removed the brain of a dog and transplanted it into another dog. After the operation, an electroencephalogram proved that the transplanted brain worked normally. This experiment proved that brain transplants do not produce rejection (i.e., the body's immune system rejects the foreign organ).

Robert White 教授

Encouraged, Prof. White's team performed head transplantation on monkeys in the same year, but the monkeys were paralyzed from the neck down due to unsuccessful connection of spinal nerves, and died of rejection reaction after 9 days. Due to repeated experimental failures and the lack of breakthroughs in related technologies, head transplantation experiments have been stagnant for a long time. In 2013, Prof. Ren Xiaoping's team conducted a more successful mouse head-swapping experiment. They removed the head of a white mouse and replaced it with a black one. Although the mouse only lived for a day at the longest, the head-swapped mouse was able to breathe on its own without relying on a ventilator.

It was the first successful experiment of its kind in the history of medicine, and this experiment became the opportunity for Cannavaro to find Ren Xiaoping.

With the media a clamor to discuss the "human head" is different, the center of public opinion, Professor Ren Xiaoping performance is relatively calm and conservative. He said in an interview that the main significance of this experiment is to provide the principle of similar surgery, the operation process, the anatomical structure of the experience. It is far away from the real human trials, let alone entering the clinic.

Some media reported that "the success rate of head transplantation reaches 90%", Ren Xiaoping responded that it is too exaggerated. "About 1,000 mice experiments were done, and the survival rate after head replacement was just 30-50 percent." As for when real human head replacement surgery will be performed, Prof. Ren said "it is impossible to determine."

Indeed, it is also now widely recognized in the medical community that the key technologies required for head replacement surgery are still very immature.

How to save the severed head; how to solve the problem of blood loss in the brain; how to connect the central, peripheral and spinal nerves; how to resolve the rejection reaction, etc., many difficulties are in front of the scientists to be solved. In the long run, human head transplantation also faces more difficult ethical and moral dilemmas. If a person succeeds in getting a new body, is he still "him"? Theoretically, he carries another person's DNA in his body, so will his offspring still be his offspring? ......

But on the bright side, if human head transplantation is really mature, many incurable diseases that have plagued mankind for years will be solved. Prof. Ren also mentioned that since the media reports, he has received many requests for help from patients with various incurable and difficult-to-survive diseases, including paraplegia, terminal cancer, and disabilities. If they can be transplanted into a new body, it will undoubtedly be a new hope in their lives.

In any case, every technological advancement is accompanied by human development and the creation of new problems. Whether it is a blessing or a curse, a paradise or a hell, only time can answer. For the time being, we don't have to expect too much or worry too much about this, just explore boldly, but don't ignore the risks.

Organ transplantation has been widely used in the medical field to save the lives of countless patients. However, for some paraplegic and terminal cancer patients, organ transplants are not effective in treating their conditions.

But two doctors have recently come up with a mind-boggling treatment option, 'head transplantation', also known as head replacement surgery. One of them is Ren Xiaoping, a professor at the Harvard Medical University, and the other is Sergio Canavero, an Italian neurosurgeon.

In terms of surgical difficulty, head replacement surgery is very difficult. The head contains many organs such as eyes, ears, mouth and nose, and most importantly, the brain and spinal cord. If the spinal cord nerves are not accurately connected during the surgery, the patient will suffer from a variety of post-surgical symptoms: for example, paralysis, or even the inability to control their own body and bizarre behavior.

So why are Prof. Ren Xiaoping and Dr. Canavero so convinced that their research will be successful?

The secret lies in the GEMINI surgical method pioneered by Canavero, and the miraculous 'cell bonding' substance polyethylene glycol. The procedure requires that the donor and head be cooled together in order to prolong cellular activity in an anaerobic state. The head is then separated, and finally, the donor's head and new body are glued together using polyethylene glycol.

In a TED X talk, Canavero used the example of a banana, comparing a squashed banana to a patient who has permanent damage to the spinal cord during surgery due to a doctor's poor knife skills, in which case the spinal cord cannot be restored. But if a sharp blade is used to make precise cuts, and polyethylene glycol is used for cellular repair, the spinal cord grows smoothly. Last November, Canavero and Ren Xiaoping had already experimented with human remains, and the operation was a perfect success.

Guys, do you support head replacement surgery? Welcome to leave a comment.

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Let's take a look at the simulation of a human head replacement: first the donor and recipient's torso is frozen and the head is rapidly cooled to below -17°C.

Localized cuts are then made to the necks of both parties and blood is transferred through tubes to the brain.

It's not as simple as just slicing and dicing; Dr. Sergio once pulled out a large banana and crushed it in a speech, likening it to spinal cord damage caused by bad knife skills, which can paralyze or even kill a person for life.

That's why advanced cutting technology becomes the key to head replacement: it can help people reduce the damage to the cortical layers, preserve the nerve units in the spinal cord that are independently responsible for movement, and restore 20 million vertebral cortical and spinal fibers.

The effect is like a banana that has been cut off by a sharp blade and can still be glued together.

Afterwards, the donor's head needs to be transferred to the recipient's neck.

Immediately glue the head to the spinal cord in the cervical cone using PEG glue.

PEG, or polyethylene glycol, is a fusion substance, and a nano-enhanced version of PEG will be used in the surgery to effectively protect neuronal cell membranes from mechanical damage and accelerate spinal cord fusion and functional recovery.

Next seamlessly connect the central nervous system, blood vessels, and muscles.

The entire transplantation process will be limited to one hour, and the blood supply to the brain will begin within 15 minutes after the vessels are connected.

The patient is predicted to be in a coma for up to a week after the surgery, and doctors will use electric shocks to promote nerve cell regeneration.

In fact, head replacement surgery is not a completely new thing, and there have been many successful cases in animals. The human quest for head replacement began as early as 1940, when Soviet scientist Vladimir Demikov did a similar experiment and successfully grafted a dog's head onto another dog's body, creating a 'two-headed dog'. By 1970, American organ transplant expert Robert White achieved the first successful head-swapping operation on a monkey, which retained its brain nerves intact after the operation, but died nine days later due to immune rejection.

Finally, the cost of head replacement surgery is up to 70 million yuan, requiring 150 senior doctors to operate for 18-26 hours in a row, no money, and we ordinary people actually have nothing to do ╮(╯_╰)╭

In the background, many friends have asked me what I think about "head-swapping", and I was invited by one of them to answer this question. Before answering, I think I must first emphasize a reality:

In fact, this so-called head-swapping surgery was done on two [corpses], not living people.

On November 17, 2017, Italian neurosurgeon Segil Canavero, along with orthopedic surgeon Ren Xiaoping of the Second Hospital of Harbin Medical University, spent 18 hours on two [cadavers] to complete this [experiment].

In fact, it was essentially anastomosing and connecting a few of the largest blood vessels and nerves, and after that, they announced to the outside world that they had successfully completed the experimental phase of the task of head-swapping. And then it was taken by the media, who like to chase hotspots, and turned into a head-swapping success with a shocking headline.

The gap between [swapping the heads on two corpses], and [swapping the heads of two normal people], the gap between the two, without saying it, can be imagined by everyone, and can be simply imagined as the gap between [a two-kicked kick] and [a spaceship on the moon].

Whether it is a foreign authoritative medical organizations, or domestic official institutions have been many people on many occasions expressed: head replacement, whether technically or ethically, are unrealistic. Simply put, head transplantation in the neck of all kinds of nerve block, like billions of cables, need to accurately distinguish which one connected to which one, and then accurately anastomosed on. This simple point is a short period of time modern medicine can not cross. Not to mention that even if connected, how to make the "cable" and then "energized".

So, the industry, more often than not, sees this so-called [head-swapping] as becoming:"a personal show in the guise of medicine" and "an inappropriate media campaign in search of hot buttons and clicks."

For more interesting and useful medical science, follow Orthopedic Surgeon Lu Yao!

When many people see the world's first successful head-swap surgery, they have one thought: whose mind is this head-swap supposed to carry out?

But actually this surgery is a specific surgical act performed on a cadaver. In other words, head-swapping surgery is technically possible.

Of course, by being able to realize it, it only means what the human mind imagines based on its own theories - "If you replace this person with a living person, it should work as well"

On the day of the successful operation, Italian neurologist Sergio Canavero was excited to announce that the world's first human head transplant had been successfully performed by him on a human remains. What makes the country even happier is that the technology was performed in China.

During the 18-hour surgery, Canavero and a team from China's Harbin Medical University connected the head of one cadaver to the spinal blood vessels and nerves of another.

This is a fairly complex systems project, and it turns out that such a systems project will probably be even more complex.

That's because two years ago, Canavero was set to perform a head replacement surgery on a Russian man with spinal muscular atrophy.

In other words, head-swapping surgery was first performed directly on living people.

But how can a mole cricket live, let alone a living person?

At the last minute, Russian Spyridonov refused surgery, preferring to live on.

That's what led to the story of the head of one body butting up against the body of another.

In fact, as early as 1959, Soviet scientists had transplanted the head of one dog, intact, into the body of another, creating the structure of a two-headed dog.

But for various reasons, the two-headed dog died after surviving only seven days. More than 20 subsequent attempts were made. None of them allowed the two-headed dog to survive for long.

Later humans experimented with monkeys as primates. However, the operation was not successful and the monkey died of immune rejection nine days later.

In this sense.Human breakthroughs have only been relatively successful at the surgical level for a very long time, and head-swapping, if it is to be performed on a living human being, may be premature.

When it comes to head transplants, most people are creeped out. However, an Italian neurosurgeon recently announced that the world's first human head transplant has been successfully performed on a human remains, and the surgery was performed in China.

The Italian neurologist who performed the surgery was Sergio Canavero, and it was performed at Harbin Medical University in China, where Prof. Ren Xiaoping was confirmed to have been involved in directing the operation.

Prof. Xiaoping Ren, who was involved in the operation, said that it took 18 hours and that they may have succeeded in finding a way to reconnect the spine, nerves, and blood vessels in a head transplant.

Prof. Ren Xiaoping also said that in the coming week, the data, process and results of the head transplant will be published in the American academic journal SNI (surgical neurology international), where all the details of the procedure will be published.

In the face of this achievement, some people questioned that it could only be considered an autopsy, while others felt that the era of real head replacement was coming. Even the initiator of the surgery, Prof. Canavero, has declared that they will soon apply for a similar surgical attempt on the patients who participated in the experiment.

Many people are very worried about this. Even if the operation can be successful, how can the accompanying ethical and moral problems be solved? However, I think that in comparison, the more horrible problem of criminalization may be more worthy of our attention.

After all, in an age where people are illegally deprived of other people's kidneys when they can have a kidney transplant, if the body also becomes a resource that can be taken normally, we can't predict whether wealthy and disabled people will then consider taking advantage of the procedure to claim the healthy bodies of ordinary people for their own.

Or even, will some old men/women who are mobility-impaired and powerless illegally deprive young people of their strong bodies? But what we can be sure of is that if the rich and powerful want to do something to the poor, most of them are powerless to fight back.

Perhaps it's too early to worry about this - after all, a procedure that is successful on a human body may not necessarily be successful on a living one. But if it can be done, does it also mean that humans don't have souls?

Nowadays, it is generally believed in the scientific community that consciousness is the result of the operation of the brain, and that it will disappear in a short period of time after a person's death because neural activities and metabolism, like the activities of other tissues and organs, have also ceased.

Francis Crick, the Nobel Prize winner in physiology/medicine, once said that the soul does not exist in religion, in philosophy, or in psychology; it lives in the nerve cells.

Christopher Kirk, a professor in the Department of Computing and Neurology at the California Institute of Technology, also says that when a person dies, there is no inter-activity of neurons and the neurotransmitters (many chemicals) that are produced and passed on, and there is no consciousness or soul.

However, the scientific community's statements have never been confirmed by the religious community, many of whom believe that people have souls and go to heaven or hell after death.

So, if the living head replacement surgery is successful, will there then be another big battle between the scientific and religious communities? Everything is unknown.

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Two surgeons based in China say a head transplant is "coming soon."

Recently, there has been a lot of buzz around the news that Sergio Canavero of Italy and Ren Xiaoping of China plan to transplant a living person's head onto a donor's body. The two surgeons have presented themselves as challenging antiquated medical authority, but are seen by many of their peers as reckless rebels. The two said the intended head donor would be someone with a degenerative disease whose mind remains active while his body continues to deteriorate.

The source of that "body" could be a donor who died of a severe head trauma, but whose body is unharmed. According to the researchers, the technique has been tested and refined on mice, a dog, a monkey and a human body. Initially, they predicted that such a procedure would be performed in the fall of 2017, but that statement has now been changed to "coming soon."

Canavero expects to carry out the procedure in China, as it will not be released by the relevant authorities in either the United States or Europe. "Western bioethicists can take a break." He said in an interview with the South China Morning Post. On the other hand, he said China wants to provide conditions for such cutting-edge work as a way to achieve a renaissance.

The news was met with skepticism. This incredible claim and radical surgical proposal did not deserve "media coverage, only scorn and condemnation." So wrote Arthur L. Caplan, chair of the Department of Medical Ethics at New York University School of Medicine, in the Chicago Tribune last December.

Critics pointed out that the preliminary and animal studies were inadequate; the technical means and results of the experiments had not been published; ethical issues had yet to be explored; and, the atmosphere of the discussion had been turned into a circus by Canaveral. In addition, since the surgery will be performed in China, the question of the source of the remains has also raised concerns.

Some bioethicists say it's a topic we should just ignore, lest we get caught up in the farce. In a recent special issue of the American Journal of Bioethics-Neuroscience, one author argues for stopping this discussion and going more into "things that can affect people's lives without adding to the ghastly fantasies."

However, I think that bioethicists should not ignore the topic of head transplantation. Maybe this time, Canavero and Ren Xiaoping won't be able to realize living head transplantation, but undoubtedly, they won't be the last ones to try it, and therefore, it's very important for us to think about the ethical implications of such an attempt.

There is no denying that the head-to-body splicing of allomorphs raises a host of thought-provoking questions about personal identity, legal and sociological definitions of self, and the bottom line of science and medicine.

According to Canavero and Ren Xiaoping's description, allogeneic head and body transplantation was the logical next step in the history of transplantation. Indeed, the history is particularly illustrious: to this day, patients survive for years after receiving heart, lung, liver, kidney and other organ transplants.

In 2017, the earliest living kidney transplant celebrated its 50th anniversary. Fifty years after a father transplanted his kidney to his daughter, both father and daughter are still alive. More recently, there have been numerous successful cases of hand, arm, leg and face transplants.In 2014, we witnessed the first successful male genital transplant. In the same year, a woman made history by giving birth to a living baby from a transplanted uterus.

As difficult as face or genital transplants are (and failures are still common), the complexity of head and body transplants is of another order of magnitude entirely.

Fundamental concerns at the scientific level

Canavero and Ren have published the results of experiments in which the heads of mice were transplanted into the bodies of rats. The failure rate was very high: in one study, out of an initial sample of 60 rats, only 14 appeared to survive past 36 hours. The pair also claim to have successfully tested the technical tool by re-fusing severed spinal cords in a dog and a monkey, respectively. However, they have not published sufficient and reliable experimental evidence, and data on the results are incomplete.

The two had claimed in media reports that both the dog and the monkey had recovered their movements. But in response, they have not published a peer-reviewed paper, nor have they indicated whether either animal regained self-awareness or whether they still have the ability to perceive. There is a picture circulating on the internet of a monkey with a gruesome ring of stitches around its neck, but that is not reliable evidence.

That's not how science is advanced. The reason for peer review and animal studies is to protect the patient, fully validate the reported results, and ensure safety. The two surgeons named the program the "Head anastomosis venture," abbreviated "HEAVEN" (meaning "heaven" in English), but they are far from providing sufficient evidence to demonstrate the safety and efficacy of head transplantation. The surgeons named the program "Head anastomosis venture" (abbreviated as "HEAVEN" in English), but they are far from providing sufficient evidence to prove the safety and efficacy of head transplants.

The key obstacle to head transplantation is the re-establishment of spinal cord connections. We have all heard about the catastrophic consequences of a severed and crushed spinal cord. In head transplants, the spinal cord is intentionally severed by the surgeon. Surprisingly, Canavero and his colleagues claim that they can rebuild spinal cord function to a great extent, except that this claim remains unproven. They claim that this technical technique is a two-step process: first, the spinal cord is severed with a very sharp knife to minimize damage; then, a chemical chelator is used to accelerate the fusion of the nerves.

But even Canavero himself admits that only 10-15% of the nerves regained function when the spinal cord was rewired. Canavero insists that his experimental animals regained some ability to move. But even if this were true, the spinal cord is also responsible for conducting sensation, proprioception (self-perception relative to the surrounding environment), pain, and so on. He has not released evidence to show that these perceptual abilities were restored.

Who is the "hybrid" after the transplant?

Some say that the chances of success for head transplants are so low, so low, that attempting it would be tantamount to murder. But even if this works, even if we join a head to a body and that person ends up alive, it's just the beginning - all the ethical questions surrounding the surgery itself, and the hybrid life it creates, will come rushing out.

Let's say a doctor transplants your head into my body and gets a person, who is that person considered? In the Western world, people tend to think that the essence of a person is his thinking, memory and emotions, which are all in his head. Since the head of the hybrid is yours, this person is naturally "you".

But this conclusion is likely to be premature for a number of reasons.

First, the human brain is constantly monitoring, responding and adapting to the body. A new body brings in new inputs, causing the brain to undergo a complete reorientation, and over time, the fundamental nature of the brain and its connectivity channels (what scientists call "connectomes") are altered.

At that time, the brain that receives me will not be the same brain that was in you. As for you, your perceived self, your memories, your connection to the world, how these things will change, we don't know for sure, but one thing is certain: this change is bound to happen.

Secondly, how much does the body influence the basic sense of self? Neither scientists nor philosophers have a clear idea of this question. But the influence of the body may not be underestimated. We are all "embodied beings," to borrow a phrase popular in the academy today, meaning that we experience the world through the inputs and responses of our bodies, not just through our heads.

The largest nerve plexus in the human body is in the brain, followed by the abdomen (the technical term is "enteric nervous system"). Often referred to as the "second brain", the enteric nervous system is so large that it operates independently of the brain; i.e., it can "make decisions" on its own without input from the brain. In fact, it uses the same neurotransmitters as the brain.

You may have heard of serotonin, which may act as a mood regulator. And in the human body, about 95% of serotonin is found in the abdomen, not in the brain. We know that the enteric nervous system has a powerful influence on a person's emotional state, but we don't know exactly what role it plays in determining our sense of self, feelings and behavior.

And, recently, research on the human microbiota exploded with a major discovery: there are more microbes in the human body than the total number of cells in the body. More than 500 species of bacteria live in the human belly, with the exact composition varying from person to person.

Various studies are increasingly proving that the microbiota affects our stress levels, fearful emotions, and even psychiatric symptoms, among other things. Researchers are currently experimenting with therapies that attempt to treat depression by altering the abdominal microbiota. In other words, we may be able to treat depression by bypassing the brain altogether.

We don't know the extent to which these microbiota systems will affect human behavior. In one study, however, scientists got two groups of mice, one shy and the other adventurous. They removed the microbiota from the abdomens of one group of mice and then transplanted the microbes from the other group. Surprisingly, the recipient mice exhibited the personality traits of the donor mice. The performance of the abdominal microbiota and the enteric nervous system lends scientific credence to the English expression "gut feeling" (gut meaning abdomen, intuition).

We also don't understand exactly what role the enteric nervous system or microbiota system plays in self-awareness. Perhaps the result of a head-body transplant is that that person ends up with a personality that is five parts body donor and five parts head donor.

Also, don't forget that even if the final hybrid person is wearing your head, his body is still mine, with my fingerprints, most of my diseases, my old injuries, and perhaps my body language, and mannerisms. It will be my genes that will be inherited by the children born to the hybrids, and it will be my parents who will be their grandparents in the genetic sense.

Question of rational allocation of resources

There are other worrisome issues with head transplants. The United States faces a severe shortage of donor organs. The average waiting period for a kidney transplant is five years, for a liver 11 months, and for a pancreas two years. A survivor can donate two kidneys, one each of heart, liver, pancreas, and perhaps other organs. It is unethical to bring in only one head transplant for that slim chance of success.

Canavero estimates that the first head transplant will cost $100 million. How many people should benefit if that money was invested in treatments and transplants that are known to work?

One day, if the severed spinal cord can really be reconnected, such a major advancement, the first people to be rescued will surely be those who are disabled by spinal cord severance or injury.

Legal issues also remain to be resolved. Who is the hybrid person in the legal sense? Is it the original owner of the "head" or the "body" in the eyes of the law? In other words, is this person you or me? The body accounts for more than 80% of the mass of a person, so in terms of mass, it is mainly me, and its handwriting may be more like mine. Also, legally speaking, who should be the children or spouse?

If, for example, this surgery leaves someone paralyzed or severely disabled (which seems likely), who should be responsible for the medical costs and long term care? (Whose insurance company should be responsible for paying for it, the head's or the body's?)

Critics say that to say the motivation behind Canaveral is more self-promotion than surgical innovation. Head transplants are a long way off. These people may be right.

But it's also entirely theoretically possible that head transplants could materialize at some point in the future. If that day does come, it becomes essential to think things through in advance.

Translated by Goose

Proofreader: Kiki

Editor: Yingzai

Source: vox.com

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This in [What problems will the first head replacement surgery face? How feasible is it? has been answered in detail under Questions.

A few more words here.

Ren Xiaoping's team is doing the work of a cook + tailor: fine dissection of the corpse is like a cook carving a flower, and then the head and torso of the corpse in the broken end of the sewing is the tailor's final garment sewing.

As for head transplants, it's unlikely that anyone alive, at least right now, will ever see it work.

This is the kind of experiment the country shouldn'tlaunch a projectFunding.

In the 1950s, the former Soviet Union did a lot of radical things to compete with the United States in science and technology, including making a lot of fake的Animal head transplantation experiments, 25 hosted double-headed dogs survived for 2 to 6 days.

It is said to be a hosted transplant because the transplanted head is simply anastomosed to the recipient dog's blood vessels to restore the blood supply and the dog's head survives temporarily. The recipient dog does not have its head cut off and the so-called transplant does not involve spinal cord manipulation.

Even then, the transplanted head had trouble surviving.

At the time, as the little brother, it was an absolutely politically correct fashion to emulate the big brother of the Soviet Union.

Domestic experiments with two-headed dogs were conducted in large numbers in the 1950s.The Second Hospital of Harbin Medical University, where Ren Xiaoping now works.Zhao Shijie set the best domestic record for a two-headed dog surviving for five days and four hours in 1956.

In the 60s and 70s, head suppression in various animals, including primate monkeys, and true head transplants after complete neck severance were performed in other countries internationally, all of which were attributed to inevitable failure - there was no possibility of success.

In recent years, Ren Xiaoping's team has repeated previous experiments with two-headed mice many times, and has also tried real head transplants with completely severed necks, with the longest survival time not exceeding one day.

Animal experiments from success are still stuck in the 1950s level, it can be said that the long march has taken the first virtual step actually 0 steps.

It is medically and ethically unlikely that any country will approve such human testing until animal testing is very well established.

And theoretically, the real success of a head transplant must be the restoration of spinal cord function by reconstruction.

This is not possible at this point in time, or even in the foreseeable long term future.

Therefore, not to mention the success of a real human head transplant, a real human head transplant trial will never become a reality.

Because, this so-called surgery means simultaneously cutting offbothphysicalliving person, one of which is the head of a living person in the full sense of the word.

Therefore, it is more of a beheading experiment than a head transplantation experiment.