BRAIN-UPLOADERZ! U R doing it Rong!
Here is an article on Pharyngula pointing out that extracting information from a brain to upload into a computer in order to replicate a persons memories and personality in a computer program is pretty much impossible:
And it quotes a guy called Gary Marcus who basically says in the foocha we'll be able to do it with our foocha tech.
But they're all arguing about the wrong thing. To upload a brain you don't touch a filthy brain! You stay away from that disgusting stuff. After all, it's pink and squishy and pretty revolting even when pan fried in breadcrumbs.
No, what you do is, you video tape a person - constantly. And then you get a neural net to observe the video and then construct new footage. (Or would that be bittage instead of footage these days?) And then, once it gets to the point that observers can't tell the difference between live footage of the human and fake footage generated by the neural net with some arbitary level of significance, you're done. You have your uploaded human being.
Now some people might complain that I haven't really uploaded a human with this method, I've just created a very convincing, Turing test passing, simulcrum. Well what do they think a human uploaded from a physical brain into a collection of zeros and ones will be, if not just a convincing simulcrum? In fact, what do they think they are now? We're just a bad copies of the person you were a year ago, and a better copy of the person we were yesterday or a minute ago. And if it gets the job done, ie. replicates the human, what's the diff? It's like complaining that my forgery of the Mona Lisa was done in watercolours instead of acrylic because somehow an acrylic copy would be more "authentic".
If you want your completely artifical brain upload that's meant to give you eternal life to be more "authentic" then don't use a machine. Marry your brother or sister and raise some children with a lack of genetic diversity. Or clone yourself. Or just don't die.
(Admittedly that last one is tricky. It always works until it doesn't.)
If people can't tell the difference between you and your image copying doppelganger, then for all practical porpoises it is you. If no one can tell the difference between you and the copy made by a video watching neural net, why should anyone care which is which? Sure, you can point out that it doesn't have a physical presence, but neither would brain scanned upload of you, and that often gets hand waved away by saying some amazing foocha technology will be able to give it a physical form indistinguishable to outside observers from your own. There, done. An exact copy of you as far as other people are concerned. And if you think that's not a proper brain upload, then it will express that opinion to your friends and family just as convincingly as you would.
So in conclusion: Brain uploads - totally doable in the future once incredibly powerful, Turing test capable, neural nets are developd. There's just no need to bother about the actual physical brain part.