Doctors complete first successful face and whole-eye transplant
scientificamerican.com
scientificamerican.com
While it is still unknown whether he will regain sight, since the May 2023 procedure, the transplanted left eye has shown remarkable signs of health, including direct blood flow to the retina—the area at the back of the eye that receives light and sends images to the brain. Although many questions remain in a case with no precedence, this groundbreaking achievement opens new possibilities for future advancements in vision therapies and related medical fields.I'll see myself out now
Now that's a euphemism for ya.
Apparently I was wrong and it wasn’t the entire eye but the cornea.
Cornea transplants can successfully restore eyesight in certain patients and it is common because the cornea doesn’t present the same tissue rejections as organs.
Just posting this in case I wasn’t alone in my misunderstanding.
(Couldn't find a reference in your link, this discusses it in the first few sentences)
((Also, why does mobile wikipedia not have any way to get the contents tab, for linking? I get hiding it by default.. but why not have it available?!))
https://www.wtamu.edu/~cbaird/sq/mobile/2015/06/25/are-there...
This is why people with corneal transplants must be very cautious about wearing contact lenses.
It was like an old VGA cable wasn’t plugged in correctly and the colors didn’t quite line up. Also had a white area appearing in the center of both eyes.
It was scary as heck. I was told not to expect full recovery due to what you stated. I am happy to report that taking my meds + time and I am back to 100%, as far as the vision at least.
The human body is very strange.
And clearly sometimes quite resilient! Congrats on the recovery
Still, as a neuroscience researcher I am very interested, if possible, in hearing a little bit more details. You mentioned a color shift. Since you compared that with a broken VGA, I assume the colors were attached to actual objects but were incorrect, right? As if someone had played with color filters in Photoshop.
Did you experience color that was "detached" from an object, like a poorly calibrated printing press that shifts one of the colors a bit?
What about the fills? Was it like a random color noise texture or a solid fill but with incorrect color?
Even if he had a dozen or so random nerves form connections and supply signals to be brain, that'd still be massively useful compared to nothing, and the brain should be able to figure out how to use that to reconstruct limited depth perception that wouldn't be possible with just one eye.
I've heard of crazy experiments done in the past, e.g. one where a blind subject was given effectively a braille device on their tongue fed from a camera, so effectively a very low resolution (it might have been 8x8), and the brain was able to start correlating the pressure signals from the tongue with "sight" and the recipient learned how to avoid obstacles using their new tongue sensor.
I just googled it and came up with these links:
https://www.scientificamerican.com/article/device-lets-blind...
If the axons in the optic nerve bundle somewhat randomly connect, is the brain able to adjust to that and re-learn how to see? Seems it may have been done in animals successfully?
Yup: but unfortunately, this is one of those things that seems to have a "critical period". (We know this because of experiments on poor defenceless kittens. Thanks, science! (But, I mean, it's decades later and it's got actual medical applications now, and we don't have to re-run the experiments because the results were all written down, so… maybe we should actually thank science for this one.))
Is this a 'cheat' to learn languages better, lol?
Here's one on visual memory in mice: https://www.lucid.news/could-ketamine-restore-child-like-bra... (links to https://www.cell.com/cell-reports/fulltext/S2211-1247(21)006...)
In general, the relevant keywords for further investigation are "ketamine neuroplasticity"
But I suppose your point is still possibly valid - just even more complex.
This is because it isn’t a single photoreceptor picking up, say, 320nm light. Instead you have a range of essentially analog responses across the red, green and blue spectrums, that the brain reconstructs into true colour as we perceive it.
Those with different receiving capabilities (on the one extreme: tetrachromia - those with 4 different colour sensors, who are exclusively women, because they’re on the C chromosome - and on the other end, those with cataracts - witness monet’s later life paintings) help to demonstrate the consistency with which the brain is able to achieve a similar qualia from the underlying stochastic impulses
Because color theory works on pretty much everyone, we can be sure that we all perceive the relative difference in colors the same way. But what green is is a figment of your consciousness. What you think color, sight, and all your other senses mean exists only in your mind. Not as a physical process in the brain, but purely as a part of whatever metaphysical process that results in consciousness.
A color is not a real, tangible thing. It's just the way your brain perceives light of a certain frequency. There is no way to describe what that experience is because there's no universal reference. You can't describe color to a blind man, after all.
The fact that we can't identify them with our current level of understanding of the workings of the brain is not very surprising - it is an extremely complex organ and our tools for understanding organs are very primitive in the grand scheme of things.
The mind is a level of abstraction up from the brain. The mind is what the brain does, not necessarily what it is. Consciousness of course relies on discrete physical reactions in the brain, but in the way that software relies on the discrete transistors in a CPU. Consciousness is the emergent behavior of the system. It exists more on an informational level than physical, even if it is a physical process.
Colour is a construct of the mind based on how we perceive light frequencies, not a tangible thing we can touch.
There is no "red" other than what we've agreed on to be red - so there's no way to swap it with "blue".
Recovery is a scary and awesome thing. When I broke my leg and had surgery I was told it was a 50/50 chance of getting nerve damage and loss of sensation to my foot. After many months of "pins and needles" and random pains, I was blessed to have full sensation restored.
I used to imagine in my head the neurons in my leg and ankle talking with each other and saying, "Hey buddy you're supposed to synapse with me, not that other guy over there".
What the future will hold, is more exciting.
It's always good when they can get an opportunity to try an approach in a "realistic" scenario to see how it turns out, rather than in a lab.
Some does come across as a bit of "let's see what happens" with the eye transplant. I don't see how what comes down to "taking this end and hooking it up to that end" could be expected to work. It's not like plugging an extension cord in, clearly. Some very small-scale structures have to line up exactly right, if its even something that can be done. But I am not in this field, so maybe it is.
It's amazing to me that people do this sort of thing as part of their career ... literally taking off a person's face, "underlying skull", and all the other stuff. Left to continue work on a sight that many wouldn't be able to even glance at during the procedure. It's surreal. Not a job for me, but it's good that there are others out there that are able to do it.
Another issue (the one that worries me) is that anaesthesia isn't always given, but neuromuscular block is, to stop the spinal reflex movements.
>Spinal reflex movements are common and full neuromuscular block is required. Hypertension and increased plasma catecholamine concentrations have been observed during surgery and attributed to spinal reflexes. These can occur spontaneously or on surgical stimulus and have prompted some to suggest that anaesthesia for organ donors is required.
That scares the hell out of me!
[PDF]https://www.bjanaesthesia.org.uk/article/S0007-0912(17)32173...
Thank you for your reply.
Wha happened to the brain transplant ?
Even if you physically put spinal nerves back together, they just don't reconnect. We can put them back together, but that's not enough.
Makes me wonder if they need to heal something burn related to get the eye functional.