It's interesting that the comments by cell biologist Len Ornstein in that thread completely omit any mention of high osmolality vitrification, which is what is practiced in cryonics. I get the impression he is not aware of Fahy's approach at all. It probably is not used in his specialty.
HOV is using extremely high concentrations of solutes to reduce the freezing point (a colligative property). That is the only way to vitrify something big like the brain. At least, until some super material is invented that lets us pull out lots of heat really fast. The trouble is that it is toxic to cells to be exposed for very long. With rabbit kidneys and small slices of brain tissue, the exposure time at warm temperatures can be very brief. So with current cryonics we can only make a morphological argument for information theoretic preservation.
With better materials that enable faster cooling, prevent the toxicity mechanisms of the cryoprotectant, and/or block ice formation non-colligatively (certain polymers do this), it is theoretically possible that we could get to a point where the cells are still viable. In that event, it would be like placing the brain in an "off state". You wouldn't be able to resume it again without a body to implant it in, but that's more likely to be on the 200-year radar than nanorepair, so the chances would be improved quite a bit. Also, I suspect more people would sign up for a process that does not involve "killing" their brain cells.
I should also mention that the wood frog is really more a counterexample of vitrification. It forms ice (which they are adapted to tolerate, unlike us), but the interior or the cells remains a slightly more concentrated liquid. It is nowhere near the concentrations used in cryonics, which are high enough to prevent freezing entirely (50-80%). A wood frog cannot survive any temperature below around -5 C.
HOV is using extremely high concentrations of solutes to reduce the freezing point (a colligative property). That is the only way to vitrify something big like the brain. At least, until some super material is invented that lets us pull out lots of heat really fast. The trouble is that it is toxic to cells to be exposed for very long. With rabbit kidneys and small slices of brain tissue, the exposure time at warm temperatures can be very brief. So with current cryonics we can only make a morphological argument for information theoretic preservation.
With better materials that enable faster cooling, prevent the toxicity mechanisms of the cryoprotectant, and/or block ice formation non-colligatively (certain polymers do this), it is theoretically possible that we could get to a point where the cells are still viable. In that event, it would be like placing the brain in an "off state". You wouldn't be able to resume it again without a body to implant it in, but that's more likely to be on the 200-year radar than nanorepair, so the chances would be improved quite a bit. Also, I suspect more people would sign up for a process that does not involve "killing" their brain cells.