
The Scientific Basis of Cryonics - apsec112
http://www.technologyreview.com/view/542601/the-science-surrounding-cryonics/
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cryoshon
Yeah, I freeze and thaw cells constantly without much trouble--just plop those
suckers in a solution of 10% DMSO and a serum-containing isotonic liquid then
throw into the freeze-assist device, then put that into the -80C freezer and
transfer it to the liquid nitrogen freezer the next morning. Everyone does it
this way, and has for years. I've always wondered if the freezing and thawing
process subtly changes cell functioning (beyond the time given to cells to
rest after being thawed), but I'm guessing if it were the case someone would
have noticed it by now.

The bugger that haunts human cryonics is that thawing is never perfect because
the cryoprotectants used to prevent ice-crystals within the cells are usually
toxic. If you freeze cells that are measured to be 100% viable/alive at the
time (very common) then thaw them using best practices, you're going to have
some cell death-- maybe 1-5% if you're fast (less time spent in toxic
cryoprotectant) and lucky. If you're unlucky or slow, you can look at 25-45%
of your originally healthy cells being dead upon completion of the thawing
process. The remaining cells are usually extremely discombobulated, and can
take days to return to their baseline. This is completely fine if you're
tooling around in a research lab or industrial lab, but even a 1% loss is
probably too much for a human brain to bear and remain the same as before.

I suppose that if you work under the assumption that the future technology
cryonics relies on for thawing will exist, cell loss during thaw will not be a
problem; I find this possibility to be fairly likely over a long time span.
Alternatively, you could assume that there will be advanced ways of restoring
brain function or generating fresh neurons after systemic damage-- quite a
stretch if you ask me, but it's conceivable. I think that ultimately the goals
of cryonics will be scientifically realizable for those who were most recently
preserved.

~~~
JoshTriplett
> Yeah, I freeze and thaw cells constantly without much trouble--just plop
> those suckers in a solution of 10% DMSO and a serum-containing isotonic
> liquid then throw into the freeze-assist device, then put that into the -80C
> freezer and transfer it to the liquid nitrogen freezer the next morning.
> Everyone does it this way, and has for years. I've always wondered if the
> freezing and thawing process subtly changes cell functioning (beyond the
> time given to cells to rest after being thawed), but I'm guessing if it were
> the case someone would have noticed it by now.

Has anyone tested this on a macroscopic creature? In particular, one complex
enough to demonstrate memory, which could be tested afterward?

I've seen one or two reports of such tests, but nothing going into detail
about the degree of function afterward.

~~~
adrianN
There are a number of amphibians that freeze during winter as part of their
natural life cycle. They seem to be fine.

~~~
larubbio
[https://www.youtube.com/watch?v=UuhEHNey37Q](https://www.youtube.com/watch?v=UuhEHNey37Q)

The above video is a short demonstration of one such amphibian

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reasonattlm
See also the scientists' open letter on cryonics, which is old enough to have
had many homes online over the years, but is now here:

[http://www.evidencebasedcryonics.org/scientists-open-
letter-...](http://www.evidencebasedcryonics.org/scientists-open-letter-on-
cryonics/)

You might also look at the Alcor FAQ for scientists:

[http://www.alcor.org/sciencefaq.htm](http://www.alcor.org/sciencefaq.htm)

Some of the ongoing information generated by the Brain Preservation
Foundation's technology prize competition is also interesting.

[http://www.brainpreservation.org/competitors/](http://www.brainpreservation.org/competitors/)

The perspective of the BPF folk is perhaps a useful calibration point for
those coming into this as a new topic; they are critical of cryonics for some
detailed technical reasons, with plenty of room for debate, think that
plastination should be developed as an alternative technology, but are firm
supporters of the concepts of brain preservation and the evidence to date for
fine structure preservation. For example, see this response to an earlier and
very shoddy article critiquing cryonics at the Technology Review:

[http://www.brainpreservation.org/ken-hayworths-personal-
resp...](http://www.brainpreservation.org/ken-hayworths-personal-response-to-
mit-technology-review-article/)

------
jimrandomh
Consider what will happen a hundred years from now, if the technology to
restore cryopreserved people is developed and used. Our descendants will look
back on our failure to do cryopreservation on any significant scale, and I
think they will judge us harshly. We, humanity, should have a billion-dollar
research project to learn how to do cryopreservation well, to improve the odds
that the brains we preserve will be repairable and to get the cost down low
enough to offer to everyone. Instead, we are condemning literally everyone to
inevitable, permanent death, not even trying to save them.

It is, without exaggeration, the greatest tragedy in the world, and it's
happening because superstition and our society's anti-superstition memetic
immune system misfired simultaneously.

~~~
tim333
I've suggested to a few people the idea of cryopreservation and I've yet to
find someone who wants it. The consensus is one life is enough. I quite like
the idea of living on but seem to be in a minority. Rather than billion-dollar
research maybe the government might be better funding a big freezer. People
might be more inclined to do it if it was a no cost option compared with
cremation / burial.

~~~
jimrandomh
It's not just a matter of putting people in a freezer; if you do that, ice
crystals will form and totally destroy the brain structures you're trying to
preserve. The actual procedure involves pumping cryoprotectants into arteries
very shortly after death (it has to be quick). Nearly all of the cost is in
the procedure performed at time of death; once that's done, long-term
refrigerated storage is trivial by comparison.

------
pron
Interesting, but I think that the psychological basis of the _belief_ in
cryonics (to the point of paying for/investing in it) is far more so.

~~~
rwallace
I was asked a while ago by a non-geek, wouldn't you have to be crazy to
believe in cryonics? My answer was, you would have to be crazy to believe
there was a one hundred percent chance it was going to work, but you wouldn't
have to be crazy to believe there was, say, a five percent chance. And that's
a lot better than the zero percent you get in a hole in the ground.

~~~
pron
Yeah but that hole in the ground doesn't cost you nearly as much, and you
don't risk the chance of waking up a brain-in-a-jar.

