• Question: What do you think would happen if brain transplants became available? Would they still be the same person?

    Asked by Hollyking to Natalie, Keith, Abbey, Aaron on 18 Nov 2015.
    • Photo: Natalie Garrett

      Natalie Garrett answered on 18 Nov 2015:

      Well given that your sense of identity is more closely related to your brain than your body, a “brain transplant” is probably not the right term, it would be more like a “body transplant”. If you woke up inside someone else’s body, I’m sure it would affect your sense of identity and take some getting used to, so although they would be the same person I guess they would change a lot too.

      There are lots of difficulties with transplants in general – the body can reject the new parts, which can lead to further complications (this is why people who have had an organ transplant have to take drugs that stop their immune system working so well, otherwise their own body would fight the transplant).

      For brains, it’s even harder, since the brain will start to die once it’s out of the original body, so there is the risk that it will be permanently damaged in the time it takes to put it into a new body. Also, it’s currently not possible to reconnect the nerves in the brain to those of a new body.

      However there is a surgeon who thinks that this will be possible one day, although some people dismiss his opinion as that of a crackpot: http://www.theguardian.com/society/2015/feb/25/first-full-body-transplant-two-years-away-surgeon-claim

      Maybe one day though?

    • Photo: Aaron Boardley

      Aaron Boardley answered on 18 Nov 2015:

      This is a good question. Are we our brains, or are we our bodies?

      If my body got a new brain, I don’t think it would still be ‘me’. Similarly, if you put my brain in someone else’s body, then I think it’s more accurate to say that that other person was now ‘me’.

      It’s hard to know where to draw the line though – how much of something do you have to swap for it to still be the same thing?

      If you like this kind of philosophical question, you should look up the ‘Ship of Theseus’, which looks at a similar problem.