Dr Sergio canavero is an Italian neurosurgeon that wants to transplant a human head to another human body possibly restoring Mobility to an otherwise fully quadriplegic patient and here's how he plans to do it two separate surgical teams will work in concert with one another in a specialized operating Suite both patients will be intubated and ventilated through a tracheotomy temperature probes will be positioned in the ear rectum nasopharynx and the bladder both patients will then be placed in the sitting neurosurgery position the recipient which is the head being transplanted will have catheters inserted into their carotid and femoral arteries which will then be attached to a cooling unit designed to lower the temperature of the blood thereby helping protect the brain during the transfer deep incisions will be made above the clavicles at the level of C5 to C6 and this is in order to expose the Carotid and vertebral arteries jugular veins the spine and any other relevant structures to the procedure the muscles of the neck will be color-coded which will help facilitate later linkage and the last cut to be made will be the spinal cords on each patient and the cuts will be performed at the exact same time the recipient's head will be suspended from a custom turning stand that will act as a crane for the procedure the head will be attached onto the donor's body via silicone tubes located at the donor Circle the Tory system the transfer will only take a few seconds since the bodies will be two and a half meters away from one another the circulation will be restored and the recipient's head and brain will be warmed up once again from there every one of the severed structures so the trachea esophagus musculature cranial nerves and even the spinal cord will be reattached plastic surgeons will then sew the skin closed ensuring scarring is minimal a test run of the procedure performed on cadavers back in 2017 took 18 hours in total which is actually half the time that Dr canavero anticipated for the real deal the recipient will remain sedated for anywhere between a few days to a few weeks after the procedure they'll then be reawakened once electrical conduction in the nervous system has been confirmed now Dr canavero isn't the first to dream of a human head transplant in the early and mid 1900s surgeons from around the world experimented with transplanting dog heads but it never worked out and the dogs would die within a few hours to occasionally leave weeks after the procedure since then various scientists have experimented with transplanting the heads of rats mice and even monkeys now no one's going to argue against the potential of restoring a patient's Mobility that would be awesome but I want you to think about this very carefully let's say the procedure is successful in the sense that the patient doesn't die on the operating table what would the patient experience if things go wrong now before we get into this I want to take a quick moment and thank the sponsor of today's video ag1 ag1 has been a sponsor of ours for years now and while their nutritional drink is not going to be very helpful when it comes to head transplants it's still enormously beneficial for the human body ag1 is foundational nutrition it's made up of 75 high quality Whole Food sourced ingredients which includes vitamins minerals superfoods probiotics and adaptogens for me I use it to support my overall gut microbiota as someone who has had significant gut issues in my past giving my gut the tools it needs to have a properly functioning gut microbiota is of the utmost importance to me all you do is take one scoop add it to eight ounces of water and Shake vigorously I mean really shake it give it some people and then from there you're just going to take a sip and carry on with your day look I'm the type of guy that is all about effortless daily habits so knowing that a significant amount of my Essential daily nutrition has been handled first thing in the morning is a huge weight off my shoulders if you're interested visit drinkag1 dot com slash human anatomy and they'll give our audience a one-year free supply of immune supporting vitamin D3 plus K2 and buy free travel packs with your first purchase you can go ahead and find that link in the description below the first reason that head transplants are potentially horrifying for the patient comes down to tissue rejection on the surface of your cells are HLA proteins which stands for human leukocyte antigen these are essentially name tags that cells display on their membranes so that other cells primarily immune cells understand they belong there when performing a transplant of any kind you want to match the HLA proteins of the donor and recipient as closely as you possibly can this way there's a hope that the immune system won't recognize the donated tissue as foreign it's kind of like trying to find the closest possible doppelganger you can a complete match is called a zero mismatch but honestly achieving a zero mismatch can be very difficult which is why a transplant can still be successful without a true match however the clinical data shows us that the better the match the better the outcomes a more distant match may work for a few years but it's not a long-term solution this type of compatibility can even be affected by the type of tissue being transplanted for instance kidneys I've shown a tremendous resilience in transplants even when there's an HLA mismatch the heart however has shown less resilience when there's a mismatch things such as age a history of previous transplants the degree of mismatch and therapies like plasmapheresis all can have an impact on the outcomes of transplantation the point here is there are a lot of different tissues being transplanted along with the head skin cartilage muscle bone tendon ligament glands nervous tissue and plenty more just think about it what would the patient experience if some of the tissues in the head are being rejected While others aren't what if the entire head gets rejected to begin with what if it's the body or parts of the body to be rejected now granted immunosuppressants and anti-rejection drugs will be essential just as they are with any transplant still though they aren't always successful in the event that they aren't 100 successful what would that look like for the patient the second reason that head transplants are potentially horrifying for the patient comes down to the millions upon millions of neurons that are traveling up and down the spinal cord it's possible for surgeons to attach the severed ends of the spinal cord but Micro surgery is not at the technological level where we can physically reattach each and every neuron that has been severed Fusion compounds such as polyethylene glycol chitosan tubes and polyurethane have shown success in certain situations and animal studies but regrowth has been minimal meaning even with the current state of micro surgery Pharmaceuticals and other compounds it's just not possible to fully reattach the millions of neurons this means that the patient will continue to have some degree of disability now Dr canavero to his credit recognizes this and claims to have a special glue-like substance that can help bring the severed neurons back together and maybe he does but if he does we still have to ask ourselves how many of the neurons and which of the neurons will actually be reconnected and just because they're reconnected does not mean that they're going to be fully functional and this leads us to the third reason that head transplants are potentially horrifying we have no idea how the brain will respond your brain whether you're aware of this or not is receiving information from every part of your body pancreas does some secreting brain knows about it stomach does some stretching brain knows about it muscles do some moving you better believe the brain knows about it incoming information like this can be broadly classified as proprioception which is essentially your brain's awareness of where your body is and it's not just your limbs and torso but there's even some vague awareness of your organs positions sizes and their shape inside your body if all of a sudden Everything Changes in the brain how will it respond will it just be like weird I imagine that the brain is going to be in some degree of shock I mean your bones muscles ligaments tendons organs skin glands fingers toes everything's going to be different but okay the brain is able to adjust and adapt to incredible situations for sure the process is called neuroplasticity and we've even discussed it in previous videos but this is a lot of change with everything everywhere all at once and on top of that we don't understand how much of our identities are wrapped up in our bodies now I don't mean that our hands feet or any other body part for that matter is capable of complex neurological processing but we don't know how our conscious perception of ourselves would change if you suddenly found yourself with someone else's digestive respiratory reproductive and cardiovascular systems when you look at advancements being made in Prosthetics implants drug design and genetics to name just a few and then combine that with advancements being made in Computing and artificial intelligence why not direct your effort that way instead of transplanting an entire human head but then and this is where things become relevant to you we have similar questions to ask ourselves when it comes to merging technology with our biology how will the brain react when humans start significantly altering their biology with synthetics will there even be a reaction we already have devices like insulin pumps and pacemakers and it doesn't seem to be creating an identity crisis with patients but we don't know how the brain will react if there are no Sensory neurons from organs delivering proprioceptive information to the brain unless of course that kind of functionality is just built directly into the implants and I kind of feel like it would have to be right or maybe we won't just want but will require some kind of brain machine interface some kind of modulating chip directly implanted into the brain or somehow interacting with the brain to help manage the lack of and new types of signals going to and from the brain I mean this is what companies such as neuralink are doing granted it's not in that specific context but I imagine that will be a requirement to handle a massive amount of technological additions and merging with our own biology and while Prosthetics and artificial tissues are nothing new up to the this point hasn't been widespread enough for the brain to be completely overcome with change so while head transplants aren't likely to go anywhere within the world of medicine things are advancing in such a way that similar issues or implications are bound to arise just simply due to technological progress so probably a good idea for us to at least start thinking about these types of things somewhat soon thanks for watching everyone be sure to click the link in the description below to begin your ag1 journey today if you found this video interesting please consider giving it a like that way YouTube is more likely to recommend it to more viewers but thanks for hanging out with me I'll see you in the next video [Music]