Ok, here is a break from the usual of my blog. I am interested in the brain since ever, and consciousness as well. I am no expert, but I read a lot on the subject. I record this only for myself later, so I don't forget, and here, you can read to make an idea.
Some thought experiment about the well known Ship of Theseus. It goes like this: imagine a ship leaving shore to go on adventures. Every day, the ship gets damaged and repaired with new material. One day it is a piece of the hull, another day, it is the sail, and so, and so. Eventually, all the elements of the ship have been changed. Is it still the same ship? One might say yes. Turns out, we are ourselves that kind of "ship", as the body regenerates the cells over our lifetime. All the cells in the body are constantly being replaced, with a few exceptions like the bones. Another exception is the brain. While most cortical neurons remain for life, there are some parts of the brain where new neurons emerge with time, like the hippocampus, but still, we are not feeling like we are a different person, our experience is that of a single individual going through life and learning from our experience.
Recently, there has been some news about the brain of a fruit-fly that was "uploaded" on a virtual reality and immediately knew how to move and act like a fruit-fly. Some could say that this is the first evidence of an uploaded living being. And it got me thinking. What would be the experience of an uploaded human being.
And so it goes to the story of the ship of Theseus. Because a "traumatic upload", where the whole brain is copied and simply modeled somewhere else is obviously creating a new kind of entity, not a continuous stream of consciousness, what happens when the uploading process is slowed. What happens if we have an interface between the human brain and the virtual reality where the brain is being loaded. The point is that, given enough time and technical advances, and I know it will come a day where it will no longer be science fiction, it will be possible to interface part of the brain to simulate missing parts.
So my question was: "What would happen if we replaced a neuron at the time with the simulated version, while the person is awake". I guess there would not be a breaking in the stream of consciousness. Because the natural neurons and the artificial neurons would act the same way physically. Unless we go for a non materialistic interpretation of consciousness, which I don't agree with, and the existence of a "soul" like phenomenon, which I also don't think is true. So the stream of consciousness would be unbroken, with the individual essentially transitioning into a virtual existence.
What happens if we speed the process? I guess it would happen faster, instead of lasting for months, it would happen in a day, within a single waking moment.
What happens if it is instantaneous? One second, you use a natural brain, the next second, it is artificial?.... Eh... This becomes complicated.
Let's assume that this would break the stream of consciousness. First of all, how would it? it is the same signals, going the same paths, only with different material? The only difference would be the physical location of the brain. It would not be possible to "vaporize the brain and replace it immediately with the alternative", so the natural brain and the artificial would need to be on separate location. Is that enough to be a reason why the stream is broken? Would the "you" die right there and be replaced by the artificial imitation of who you were? How could it be, if the signals are all the same? Anyway, the stream is somehow broken there. This means that somewhere in the middle is a moment where the breaking of the stream happens. Is it when the first neuron gets replaced? when 50% of the neurons get replaced? when the last is replaced? I think it doesn't make sense to say that given a portion of the brain replaced, there is a breaking in the stream. So I would say that the stream doesn't break during that process.
So now, let's assume that the instantaneous replacement doesn't break the stream of consciousness, and you go from natural brain to artificial brain in an instant. More importantly, imagine that your original brain is not "destroyed" during the copying process, but simply scanned. You still have your brain, but another entire copy of you, brain and body is created and uploaded to a virtual reality. Do you have a split consciousness there? Would you somehow experience both things at the same time? It feels like it is not possible. Well, no one ever tried, maybe it is possible. What would that mean? I guess it all boils down to what it is to be conscious.
After all, it is obvious that we are not aware of being in someone else's body, so our conscience is only linked to our own. It all points to the fact that our experience is encoded into some engram in our brain, and our conscious experience is pulling memory from there. As some people say, the consciousness is really just an emergent phenomenon that happens after some systems become too complex. And here is the kicker: What says that your stream of consciousness is really unbroken? Actually, it is not. Everyday, every night, you fall asleep. I fall asleep. And during a brief moment, you become unaware of your environment, unaware of everything. Only basic functions remain. You could say that your stream of consciousness is actually just a few hours, not days, especially not years. What if the new person waking up is not the same person as the one yesterday? You can't make the link actually of your conscious experience moving from one day to the next. What if uploading is the same? you go to sleep, and something else wakes up, believing it is you. The only difference is that it has a different body, but all the memories are the same. And from his perspective, the stream of consciousness is preserved, bare from falling asleep and waking up.
So here is my idea, after all this "thinking aloud". The conscious part of you is aware it is you because you can only have a single body, and the memory match that body. If all your brain engram and the mechanism is copied and transferred in a virtual reality, I think that the being waking in that virtual body will believe to be the same that went to sleep just before the upload. And then, the question is, can you upload yourself in the cloud and continue living there? It doesn't really matter as you, the consciousness of now, will not see the next day anyway. The consciousness that will emerge from the virtual brain with the memory engram of you will wake and live there for a moment, maybe forever given the lack of requirement to shut down in the virtual world, or it will shut down, but again, who cares, this is the way it has always been, consciousness just emerges at the next reboot, and this is all that matters.
This goes back to science fiction, like Star Trek, or Stargate. In Star Trek and Stargate, there are devices that transfer the body from one place to another, almost instantaneously. Teleportation. But to occur, the original body is "deconstructed" by the machine, and reconstructed elsewhere. And some people argue that it is hardly a valid way to teleport because you die every time you use it. My point really is that it basically doesn't matter. If consciousness works the way I wrote before, it is no different that falling asleep and waking up elsewhere. Since your original body will eventually go to sleep at some point, the consciousness in there will stop also at that point, before waking up, rebooting, the next day. Be it in the same bed, or on another planet. The next reboot of consciousness will not see a difference, and will still believe of a continuous stream.
