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categories: ["bodies"]categories: ["bodies"]tags: ["transplantation", "spinal cord", "neurosurgery", "medical ethics", "identity", "fringe science"]tags: ["transplantation", "spinal cord", "neurosurgery", "medical ethics", "identity", "fringe science"]summary: "The proposed transfer of a living human head onto a donor body, blocked chiefly by the inability to reconnect a severed spinal cord and rejected by mainstream neurosurgery."summary: "The proposed transfer of a living human head onto a donor body, blocked chiefly by the inability to reconnect a severed spinal cord and rejected by mainstream neurosurgery."updated: "2026-08-23"updated: "2026-10-29"humanEvidence: "No human attempt has been made; living-subject work stops at Demikhov's 1950s dogs and White's 1970 rhesus monkeys, whose cords were never joined, and the 2017 human procedure was a rehearsal on two cadavers."humanEvidence: "No human attempt has been made; living-subject work stops at Demikhov's 1950s dogs and White's 1970 rhesus monkeys, whose cords were never joined, and the 2017 human procedure was a rehearsal on two cadavers."------ lines 26–32 → 26–3212 unchanged lines not shown
}}`````` **Head transplantation** is the proposed surgical transfer of a living head onto a body from a different individual, so that the recipient's brain is supplied by a new circulatory and musculoskeletal system. The procedure is more accurately called a body transplant, since the person who would survive is the one attached to the head. No human attempt has been made. The obstacle that makes it implausible is not surgical technique but the fact that a completely severed spinal cord cannot be repaired, and every proposal for performing the operation depends on solving that problem first.**Head transplantation** is the proposed surgical transfer of a living head onto a body from a different individual, so that the recipient's brain is supplied by a new circulatory and musculoskeletal system. The procedure is more accurately called a body transplant, since the person who would survive is the one attached to the head. No human attempt has been made. What makes it implausible is the spinal cord rather than surgical technique: a completely severed cord cannot be repaired, and every proposal for performing the operation depends on solving that problem first. ## Animal precedents## Animal precedents lines 34–40 → 34–401 unchanged line not shown
In the 1950s Vladimir Demikhov, a Soviet surgeon who did foundational work on cardiac and pulmonary transplantation, created dogs bearing a second head and forelimbs grafted onto the neck of an adult host. The grafted heads were conscious and could lap fluid. The animals survived days, dying of rejection.In the 1950s Vladimir Demikhov, a Soviet surgeon who did foundational work on cardiac and pulmonary transplantation, created dogs bearing a second head and forelimbs grafted onto the neck of an adult host. The grafted heads were conscious and could lap fluid. The animals survived days, dying of rejection. Robert White, a neurosurgeon at Case Western Reserve University, performed the most technically advanced version in 1970, transferring the head of one rhesus monkey onto the body of another with vascular anastomosis and hypothermic protection. The transplanted head regained consciousness, tracked with its eyes, and responded to stimuli; the animals survived for periods reported as hours to a few days before succumbing to rejection or complications.[^white1971] Crucially, White made no attempt to join the spinal cords. The animals were quadriplegic and ventilated, and White himself described the result as a demonstration that the brain could be maintained on a foreign circulation, not as a functional transplant.Robert White, a neurosurgeon at Case Western Reserve University, performed the most technically advanced version in 1970, transferring the head of one rhesus monkey onto the body of another with vascular anastomosis and hypothermic protection. The transplanted head regained consciousness, tracked with its eyes, and responded to stimuli; the animals survived for periods reported as hours to a few days before succumbing to rejection or complications.[^white1971] White made no attempt to join the spinal cords. The animals were quadriplegic and ventilated, and White himself described the result as a demonstration that the brain could be maintained on a foreign circulation, not as a functional transplant. ## The modern proposal## The modern proposal lines 53–59 → 53–5912 unchanged lines not shown
Restoring function would require far more than membrane fusion. Millions of axons would have to reconnect, each to a target of the appropriate class, in a topographically correct arrangement, and the resulting circuit would have to be usable by a brain whose motor map was built for a different body. Polyethylene glycol can fuse the membranes of adjacent cut axons in laboratory preparations; it does not perform routing.Restoring function would require far more than membrane fusion. Millions of axons would have to reconnect, each to a target of the appropriate class, in a topographically correct arrangement, and the resulting circuit would have to be usable by a brain whose motor map was built for a different body. Polyethylene glycol can fuse the membranes of adjacent cut axons in laboratory preparations; it does not perform routing. The scale of the difficulty was underlined by a 2023 transplant at NYU Langone in which a patient received a partial face transplant that included an entire eye. The globe survived with perfused retina, which was itself a first.[^ceradini2024] Vision was not restored, because the optic nerve is a central tract and could not be reconnected — a single nerve, under ideal circumstances, with the world's attention on it. Restoring sight after optic nerve loss currently requires bypassing the nerve altogether, which is what a cortical visual prosthesis attempts and why the devices in [[retinal-implant]] exist.The scale of the difficulty was underlined by a 2023 transplant at NYU Langone in which a patient received a partial face transplant that included an entire eye. The globe survived with perfused retina, which was itself a first.[^ceradini2024] Vision was not restored, because the optic nerve is a central tract and could not be reconnected, even though it was a single nerve, handled under ideal circumstances, with the world's attention on it. Restoring sight after optic nerve loss currently requires bypassing the nerve altogether, which is what a cortical visual prosthesis attempts and why the devices in [[retinal-implant]] exist. ## Other barriers## Other barriers lines 69–79 → 69–799 unchanged lines not shown
Even granting technical success, the procedure raises questions the surgical literature does not usually face. The resulting person would carry another individual's genome in every cell below the neck, including the gametes, so any children conceived would be genetically the donor's. Legal identity, in most systems, would follow the head, but no statute anywhere addresses the case. The psychological consequences of waking in an unfamiliar body are unknown; limb transplant recipients have occasionally requested removal of a functioning graft, and a whole body is not comparable.Even granting technical success, the procedure raises questions the surgical literature does not usually face. The resulting person would carry another individual's genome in every cell below the neck, including the gametes, so any children conceived would be genetically the donor's. Legal identity, in most systems, would follow the head, but no statute anywhere addresses the case. The psychological consequences of waking in an unfamiliar body are unknown; limb transplant recipients have occasionally requested removal of a functioning graft, and a whole body is not comparable. The philosophical question is thinner than it looks. Almost every theory of personal identity locates the person with the brain, so a head transplant is a body transplant and the identity puzzle is mild compared with the cases discussed in [[personal-identity-and-continuity]] and [[teleportation-problem]]. The serious ethical objection is not metaphysical but clinical: performing an irreversible operation whose central step has never worked in any animal, on a patient who is typically disabled rather than dying, and whose realistic outcome is death or a state worse than the one they began in. Appeals to [[morphological-freedom]] do not settle this, since a right to modify one's own body is generally held to presuppose that the modification is technically possible and the consent adequately informed.The philosophical question is thinner than it looks. Almost every theory of personal identity locates the person with the brain, so a head transplant is a body transplant and the identity puzzle is mild compared with the cases discussed in [[personal-identity-and-continuity]] and [[teleportation-problem]]. The serious ethical objection is clinical rather than metaphysical: performing an irreversible operation whose central step has never worked in any animal, on a patient who is typically disabled rather than dying, and whose realistic outcome is death or a state worse than the one they began in. Appeals to [[morphological-freedom]] do not settle this, since a right to modify one's own body is generally held to presuppose that the modification is technically possible and the consent adequately informed. ## Where the idea stands## Where the idea stands Head transplantation occupies a peculiar position: it is not disproved, merely dependent on a prerequisite that nobody can supply. If complete spinal cord transection became repairable, the achievement would transform the treatment of the more than 15 million people estimated to be living with spinal cord injury worldwide,[^who2024] and that population — not head transplant candidates — is where such a technique would be used first and where its success would be measured.Head transplantation occupies a peculiar position: it is not disproved, merely dependent on a prerequisite that nobody can supply. If complete spinal cord transection became repairable, the achievement would transform the treatment of the more than 15 million people estimated to be living with spinal cord injury worldwide,[^who2024] and that population, rather than head transplant candidates, is where such a technique would be used first and where its success would be measured. The motivations offered for the procedure are better served by other approaches. Spinal muscular atrophy, the condition of the volunteer who was announced and then withdrew, now has approved gene therapies of the kind described in [[somatic-gene-therapy]], which arrived within a few years of the head transplant proposal and changed the prognosis for the disease it was meant to address. For other degenerative conditions the realistic paths remain gene and cell therapy and assistive technology, including [[brain-computer-interface]] control of external devices and [[exoskeleton|powered exoskeletons]]. For the ambition of escaping a failing body altogether, the relevant articles are [[cryonics]], [[whole-brain-emulation]], [[mind-uploading]] and [[neuroprosthetics]], each of which faces its own unsolved problems but none of which requires reconnecting a spinal cord this year.The motivations offered for the procedure are better served by other approaches. Spinal muscular atrophy, the condition of the volunteer who was announced and then withdrew, now has approved gene therapies of the kind described in [[somatic-gene-therapy]], which arrived within a few years of the head transplant proposal and changed the prognosis for the disease it was meant to address. For other degenerative conditions the realistic paths remain gene and cell therapy and assistive technology, including [[brain-computer-interface]] control of external devices and [[exoskeleton|powered exoskeletons]]. For the ambition of escaping a failing body altogether, the relevant articles are [[cryonics]], [[whole-brain-emulation]], [[mind-uploading]] and [[neuroprosthetics]], each of which faces its own unsolved problems but none of which requires reconnecting a spinal cord this year. removed, struck through added, underlinedLine numbers count the serialised markdown of each revision, frontmatter included.
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