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How Human Head Transplants Could Work

Giving and Receiving: Organ Transplants in a Nutshell
Visually challenged youth in India hold posters during a campaign to create awareness about eye donation in Kolkata on Aug. 27, 2014.
Visually challenged youth in India hold posters during a campaign to create awareness about eye donation in Kolkata on Aug. 27, 2014.
Dibyangshu Sarkar/AFP/Getty Images

Often when you get your driver's license, you have the opportunity to sign up as a potential organ donor. How does the rest of the organ donation story play out? Let's look at it from the two opposite points of view: the recipient of the organ and the donor.

To become eligible to receive an organ (or a few organs) from a donor, patients must be in such poor health that one of their organs is on the verge of failure. Kidney failure, heart disease and lung disease are all conditions where a patient could benefit from a transplant.

Many people don't realize, however, that transplants go beyond organs like heart, lungs and kidneys and include tissue donation as well. For example, people who are severely burned may receive skin transplants; some conditions that cause blindness can be corrected with a cornea transplant and doctors even have performed transplants with tendons, bone and cartilage.

Once a patient meets the criteria to receive an organ, he or she gets placed on a waiting list. In the United States, this database is maintained by the United Network for Organ Sharing (UNOS). UNOS is responsible for matching organ recipients with donors as they become available. Once on the list, the patient waits for the call, which may take months to several years, depending on the organ [source: Gift of Life Donor Program]. Sometimes it doesn't come in time.

People can sign up to be organ donors anytime by registering through UNOS or at the Department of Motor Vehicles when obtaining a driver's license. If an incident occurs where a person suffers irreversible loss of all brain function and is declared brain-dead, thereby making their organs eligible for donation, the family still must consent to the donation. From there, the process moves quickly to make the match to a recipient and get the operation going.

That's the general process for a regular organ transplant. But we're not talking about a regular one; we're talking about transplanting a head. First of all, this procedure would obviously not work for a living donor. Transplants involving living donors happen in situations where a living person can donate an organ (namely kidney or liver) to another without dying. You clearly cannot donate your head without dying. In theory, a head transplant could occur between living donors if they swapped heads; however, this would be a very costly elective surgery (if even ever approved), as there is no medical condition where trading heads would be suggested as a form of treatment. So what we're looking at in the case of a head transplant is a situation where you have someone with a condition that leaves the mind intact but devastates the body.

Perhaps it's better to think of it as a body transplant, as the transplant recipient is really keeping his or her own head but receiving a new body. Technically, you are moving the head on to a new body, but that's only because the head is smaller and easier to move than an entire body.

Could this ever happen? Keep reading to learn more about the experiments that have paved the way toward bringing this operation closer to reality.