A 15-year-old asked the question — receiving an answer from an associate professor of psychology at Georgia Institute of Technology. They write (on The Conversation) that "As a brain scientist who studies perception, I fully expect mind uploading to one day be a reality. "But as of today, we're nowhere close..."Replicating all that complexity will be extraordinarily difficult. One requirement: The uploaded brain needs the same inputs it always had. In other words, the external world must be available to it. Even cloistered inside a computer, you would still need a simulation of your senses, a reproduction of the ability to see, hear, smell, touch, feel — as well as move, blink, detect your heart rate, set your circadian rhythm and do thousands of other things... For now, researchers don't have the computing power, much less the scientific knowledge, to perform such simulations. The first task for a successful mind upload: Scanning, then mapping the complete 3D structure of the human brain. This requires the equivalent of an extraordinarily sophisticated MRI machine that could detail the brain in an advanced way. At the moment, scientists are only at the very early stages of brain mapping — which includes the entire brain of a fly and tiny portions of a mouse brain. In a few decades, a complete map of the human brain may be possible. Yet even capturing the identities of all 86 billion neurons, all smaller than a pinhead, plus their trillions of connections, still isn't enough. Uploading this information by itself into a computer won't accomplish much. That's because each neuron constantly adjusts its functioning, and that has to be modeled, too. It's hard to know how many levels down researchers must go to make the simulated brain work. Is it enough to stop at the molecular level? Right now, no one knows. Knowing how the brain computes things might provide a shortcut. That would let researchers simulate only the essential parts of the brain, and not all biological idiosyncrasies. Here's another way: Replace the 86 billion real neurons with artificial ones, one at a time. That approach would make mind uploading much easier. Right now, though, scientists can't replace even a single real neuron with an artificial one. But keep in mind the pace of technology is accelerating exponentially. It's reasonable to expect spectacular improvements in computing power and artificial intelligence in the coming decades. One other thing is certain: Mind uploading will certainly have no problem finding funding. Many billionaires appear glad to part with lots of their money for a shot at living forever.Although the challenges are enormous and the path forward uncertain, I believe that one day, mind uploading will be a reality. "The most optimistic forecasts pinpoint the year 2045, only 20 years from now. Others say the end of this century. "But in my mind, both of these predictions are probably too optimistic. I would be shocked if mind uploading works in the next 100 years. "But it might happen in 200..."Read more of this story at Slashdot.