[ExI] Cryonics Alexandre Erler and bad philosophy

John Clark johnkclark at gmail.com
Thu Nov 23 20:10:32 UTC 2017


In the current issue of Cryonics Alexandre Erler comments on the following
research article by McIntyre and Fahy about preserving the information in
brains using a new process called aldehyde-stabilized cryopreservation
(ASC), and Erler doesn't much like what he sees.  You can download a PDF of
the McIntyre and Fahy article here:

https://www.sciencedirect.com/science/article/pii/S001122401500245X

This method is quite different from the way Alcor preserves brains and in
my opinion superior, but Erier doesn't like it for philosophical reasons
that I have to say seem downright silly to me. Basically what they did is
fix the molecules in place with glutaraldehyde (the stuff in the wart
removing lotion you can get at the drugstore ) then they infused ethylene
glycol as a cryoprotectant and then cooled the brains down to -135 C where
they became vitrified.  After rewarming the brains were examined and  "*show
exquisite preservation of anatomical detail after vitrification and
rewarming, with virtually no identifiable artifacts relative to controls*."

So can Alcor's method match that?  Erler says he doesn't know because with
Alcor's method "the brain shrinks to almost 50% of its natural size due to
osmotic dehydration hindering our ability to establish the quality of
ultrastructure preservation".  Well yes, I imagine such shrinkage would
distort things and make it harder to see fine details, McIntyre and Fahy
think so too:

"
*For the purposes of connectomics, this dehydration is undesirable because
it distorts the brain's ultrastructure and causes difficulties in tracing
fine​ neural processes*. "

But there is no shrinkage with the new method. After keeping the brains at
-135 C for several days they then rewarmed them and examined them with a
electron microscope. This is what they found:

*"Rabbit brains upon dissection revealed no cracks resulting from the
vitrification or rewarming processes. Brain weights were commensurate with
control brains, and we found no retraction of the brains from their skulls.
Control rabbit brains displayed excellent ultrastructural preservation.
[...] All 8 rabbit brains preserved using ASC consistently displayed
ultrastructural preservation indistinguishable from that of controls [...]
Intracellular organelles are also well preserved: rough endoplasmic
reticulum is clear and compact, and the mitochondria appear normal  [...]
There are several synapses present, with clear pre-synaptic vesicles and
well defined, darkly stained post-synaptic densities [...] All capillaries
are open and clear of debris, there are no ‘‘dark’’ cells, and there is no
obvious mechanical or osmotic disruption or distortion of any cells.  [...]
We also observed no signs of ice crystal artifacts in any of our
ASC-processed brains. [...] . Vitrified storage at -135 C should enable
essentially indefinite storage of brain tissue with no degradation due to
suppressed molecular motion in the vitrified state. [...]The aldehydes
immediately stabilize the fine structure of the brain to an extent
sufficient for connectomics research, meeting our goal of high-quality
preservation. [...]  ASC is scalable to because the  chemicals are
delivered via perfusion, which enables easy scaling to brains of any size;
vitrification ensures that the ultrastructure of the brain will not degrade
even over very long storage times, processes were easily traceable and
synapses were crisp"*

So much for that old canard about a frozen brain resulting in mush. It
seems pretty clear to me that the ASC method is better at preserving brain
information and Alcor should switch over to it unless financial reasons
make it impractical, and I don't think wart lotion is all that expensive.
But the thing that bothers Alexandre Erler is not the expense but the fact
that although the information about the brain is preserved the fixative
would render the brain itself unviable, it would be easier to use the
information to make another brain (or upload the brain software) than it
would be to remove all the molecules of glutaraldehyde from the original
brain so it can be restarted. Erler fears that the duplicate brain might
not *really* be you even if all the information in both was identical, he
wants to keep the "original" brain.

But what exactly is so original about the "original"? Atoms are generic,
our names are not scratched on
​the atoms in our bodies​
, not even
​on ​
the atoms in our brain.  And besides
​,​
atoms are constantly shifting in and out of our bodies anyway, today your
brain is literally made of last years mashed potatoes. It seems to me if we
are going to have any chance of escaping oblivion we need to totally
embrace rationality
​,​
and that means we should go for whatever method that best preserve brain
information regardless of what happens to "the original". Cryonicists often
criticize others for failing to be rational about life and death, but with
talk about "the original" and a immaterial "something" that a copied brain
would lack we are doing the same thing; if we're going to go down that road
we might as well abandon science altogether and stick with traditional
religion and hope that mumbo jumbo will bring us immortality.
​ I agree 100% with ​
McIntyre and Fahy
​ that we don't ​"
*need to preserve the biological viability of brain tissue; the primary
criterion for success is instead to maintain the delicate​ ​ultrastructural
appearance of the brain*
*​*"​
.
​

​John K Clark​
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