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Dolores1984 comments on [LINK] blog on cryonics by someone who freezes things in a cell bio lab - Less Wrong
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Per PZ Myers, the state of the art in neural preservation doesn't recoverably preserve usable amounts of state in zebrafish brains, which are a few hundred microns on a side. How thin slices were you thinking of? And how fast were you going to be slicing?
Which is obvious nonsense. PZ Meyers thinks we need atom-scale accuracy in our preservation. Were that the case, a sharp blow to the head or a hot cup of coffee would render you information theoretically-dead. If you want to study living cell biology, frozen to nanosecond accuracy, then, no, we can't do that for large systems. If you want extremely accurate synaptic and glial structural preservation, with maintenance of gene expressions and approximate internal chemical state (minus some cryoprotectant-induced denaturing), then we absolutely can do that, and there's a very strong case to be made that that's adequate for a full functional reconstruction of a human mind.
As you'll see if you read his text, he's responding to proposals to emulate a brain without understanding how it all works, and is noting just how fine you'd need to actually go to do that.
I've heard the case made at length, but not of, e.g., a C. elegans that's learnt something, been frozen and shows it stil remembers it after it's unfrozen (to name one obvious experiment that, last time this precise Myers article was discussed, apparently no-one had ever done) or something of similar evidentiary value. Experiment beats arguing why you don't need an experiment. Edit: Not the last time this Myers article was discussed, but the discussion of kalla724's "what on earth" neuroscientist's opinion on cryonics practice.
Right, but (virtually) nobody is actually proposing doing that. It's obviously stupid to try from chemical first principles. Cells might be another story. That's why we're studying neurons and glial cells to improve our computational models of them. We're pretty close to having adequate neuron models, though glia are probably still five to ten years off.
I believe there's at least one project working on exactly the experiment you describe. Unfortunately, C. elegans is a tough case study for a few reasons. If it turns out that they can't do it, I'll update then.
You might find this earlier discussion useful on how far we've gotten with emulating C elegans: http://lesswrong.com/lw/88g/whole_brain_emulation_looking_at_progress_on_c/