The term 'whole brain emulation' sounds more scientific than it does science fiction like, which may bode well for its credibility as a genuine academic discipline and area for inquiry.
Sandberg presented his whole brain emulation roadmap which had a flowchart like quality to it -- which he quipped must be scientific because it was filled with arrows.
Simulating memory could be very complex, possibly involving chemical transference in cells or drilling right down to the molecular level. We may even have to go down to the quantum level, but no neuroscientist that Anders knows takes that possibility seriously.
Validation has been overlooked in discussions of uploading/downloading. In other words, we don't know if our simulations will convert to reality or not. We need to find ways of testing -- to take pieces of neuron tissue and know exactly how it's working. The retina is a good candidate for beginning this sort of research.
Scanning technologies are painfully slow; research to improve this aspects needs to happen. Electron microscopy will be required. It would be nice to to get down to 50 nanometers. Destructive scanning may be necessary in some cases.
Functional simulation of neurons is relatively easy and is currently being done in research labs.
In regards to computer power, memory storage will not be a bottleneck at all. In terms of raw power, we should plot and plan our emulations around the expected time-frames for processing power (i.e. Moore's Law graphs).
Interesting ethical problems emerge about testing with non-human animals and their potential suffering. It will also be difficult to suss subjective data from animals -- like getting their perspective on changes to perception, discomfort level, etc. Anders wants to write an entire paper on the matter.
There are also significant differences between large and small brains (like mouse brains).
This will be a massive iterative process that will take lots of time and effort; it will also be driven by technological advances. There are still a large number of purely philosophical challenges. For example, we may find that scanning is not a panacea that will always reveal function.
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