Sparks Brain Preservation

I don't think we currently have the technology to scan an entire human brain. I have another scenario for how it might work, though. We need something that can scan the whole brain without subdividing it first. We could physically mill off 25 nm at a time across the entire brain. The newly exposed surface would be scanned and then another 25 nm milled. Repeat 6,000,000 times. But the tricky part is that I really don't think electron microscopy could work for the scanning of each layer in that scenario. Staining and embedding are just really not feasible. I think what we might do instead would be to apply tags to the surface, and then drag small electrode arrays across the surface. For example, one array head might be about 10 microns square and contain a few thousand electrodes on it. The surface of the head would be smooth, with each of the electrode tips flush with the smooth surface. The electrodes would all be spaced out to not interfere with each other. They would be engineered to pick up the signals of the tags. Each electrode tip would be about 4 nm in diameter, and the resolution would be about 4 nm, the same as current electron microscopes. We could obviously also drag thousands of these heads across the surface at once for massive parallelism. We probably have the technology right now to just barely build these, but nobody is nearly motivated enough yet. But maybe 20 years from now.