By Aaron, our Design and Layout Editor
Having transplanted skin, hands, livers and many other body parts, is it only a matter of time before humanity is equipped to tackle a head? Aaron explores the implications.
Have you ever dreamed of having a twenty-year-old body – as in a transplanted body from the head down? All fresh and new, everything working, no saggy bits, no wrinkles and everything in peak condition. No? Maybe just me then. Scientists have been looking at this possibility for many years, not for cosmetic reasons, but in the hope of giving quadriplegics a new chance of life with a fully functioning body. Exploratory head transplants were conducted on dogs as early as the 1950s.
You mean this has been done before?
Actually yes, and with some degree of success. Dogs, rats, and over a thousand mice and monkeys have all been experimented on, and some have lived for a few hours with moving limbs and responsive brain waves. But surviving for just a few hours after surgery is obviously not satisfactory from a human point of view.
In 2016, Valery Spiridonov, a Russian man who suffers from a muscle-wasting disease, became the first person to volunteer for a head transplant. The extremely complex surgical procedure would have included the following steps:
Freeze the head and body to -15°c to stop brain cells from dying
Neck partially cut through, blood vessels connected via tubes
36 hour operation involving 150 medical staff
Spinal cord glued together to encourage regrowth of neural pathways
Muscles, veins, and oesophagus attached
Induced coma for four weeks
Spiridonov was eager to undergo the procedure until 2018 when, after having a child with his partner, he cancelled.
Some testing on cadavers has been undertaken, with a full transplant taking 18 hours with all the extremely complex connections that need to be made, including the brain, spinal column, skin, bone, cartilage, and so forth. The potential for tissue rejection is of course very great. Even with a close match of Human Leukocyte Antigen (HLA) proteins to minimise the risk, the patient would require lifelong immunosuppressive therapy, which comes with its own set of severe complications and risks.
Despite advances in medical technology, the connection of the spinal column remains a complex challenge, due to its intricate structure. While surgeries to repair veins, arteries, and certain aspects of the skeletal system have become relatively routine, the spinal column's complexity goes beyond current standard procedures. Researchers are exploring the use of a specialised adhesive designed to promote tissue regrowth in spinal column repairs. However, this method is still in the experimental phase, and long-term studies have yet to demonstrate consistently positive outcomes.
“Even with the current state of microsurgery, pharmaceuticals and other compounds, it’s just not possible to fully reattach the millions of neurons.” Institute of Human Anatomy
Where should humanists sit on this?
Humanists follow the science, and if head transplants became feasible at some point in the future, helping people to live happy, long and fulfilled lives when they otherwise wouldn't have, then I can see most of us supporting the idea. But it seems that, for now, it's no more than a speculative idea.
As detailed by the Institute of Human Anatomy (see link below), numerous complications can arise if any portion of the spinal column fails to properly connect. The brain may suddenly lose vast amounts of information previously acquired from the old body, necessitating the formation of new neural connections with every part of the new body. This includes all organs, sensory systems, and nerve endings. While tissue rejection presents a significant challenge, the incomplete integration of the spinal column introduces an entirely different set of complexities.
Will successful head transplants be achieved in the foreseeable future? How keen would you be to undergo such a procedure? What are the ethical and resource implications of spending this amount of time, money and surgeon capacity on repairing one person, when the entire team could, in the same timeframe, undertake hundreds of other body repairs?
There's a notable episode from the original Star Trek series titled “Spock’s Brain” (Season 3, Episode 1), where Spock’s brain is stolen, and his body is kept alive mechanically while the crew of the USS Enterprise searches for it. But even Star Trek has never gone so far as to transplant a head onto a new body. Was this through lack of imagination on the part of the writers, or is this still too outlandish to contemplate? Why not comment below?
“While I might trust the doctor to remove a splinter or lance a boil, I do not believe he has the knowledge to restore a brain.” Spock
Links
World's First Head Transplant Recipient Wants A Better Life – Good Morning Britain
The operation video in CGI
How Long Does a Head Transplant Take? Institute of Human Anatomy
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