X-Message-Number: 6
From: Kevin Q. Brown
Subject: preservation alternatives
Date: 2 Aug 1988
There may be more than one way to save yourself. Here are some alternatives
being considered by some people today:
(A) freezing the whole body in liquid nitrogen (-196 C)
(B) " " " " in dry ice (-79 C)
(C) " " " " in artic tundra
(D) freezing the head only in liquid nitrogen
(E) freezing the brain only in liquid nitrogen
(F) vitrifying rather than freezing the whole body, head, or brain
(G) dehydrating rather than freezing the whole body, head, or brain
(H) downloading the information in the brain into an electronic medium
I have added some commentary below for each of these options.
Freezing the Whole Body in Liquid Nitrogen
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This is the original recommendation offered by Robert Ettinger in his book
"The Prospect of Immortality". It is still the preferred method of much of the
cryonics community.
Freezing the Whole Body in Dry Ice
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A French woman (Madame Monique Martineau) is currently being preserved at -55 C
(Nov. 1987 issue of The Immortalist), which is not quite as cold as dry ice.
According to the Arrhenius equation, though, the reaction rate at this (or even
dry ice) temperature is much greater than at liquid nitrogen temperature and
the long-term preservation of her memory/personality is questionable.
Freezing the Whole Body in Artic Tundra
---------------------------------------
The July 1988 issue of The Immortalist mentions someone who (for financial
reasons) had to settle for interrment in the Canadian permafrost. This may
be sufficiently cold for building a clone of the man (from the DNA) a couple
of centuries from now, but is useless for preserving his personality.
Freezing the Head Only in Liquid Nitrogen
-----------------------------------------
This is currently one of the more controversial options among the three
cryonics organizations. Alcor offers both whole body and neuro suspension in
liquid nitrogen. ACS (American Cryonics Society) can do both whole body and
neuro suspension, but wants to do only whole body. CI (Cryonics Institute)
offers only whole body. Alcor's paper "Neuropreservation: Advantages and
Disadvantages" (available from Alcor for 50 cents or less) describes the case
for neurosuspension in detail.
An undisputed advantage of the neuro option (over whole body) is cost, both for
suspension and for maintenance (liquid nitrogen required to remain frozen).
Another advantage is the quality of perfusion with cryoprotectants attained
during suspension. Each organ has its own optimal perfusion protocol and when
the suspension can concentrate on the head only, the quality of perfusion of
the brain does not have to be compromised to attain better perfusion of other
parts of the body. Another important advantage of the neuro option is mobility.
Whole body suspendees are stored in large, bulky containers that are hard to
transport whereas the neuro suspendees are stored in a concrete vault on wheels
that can be quickly hauled away in case of fire or other emergency. (Also,
if necessary, they can be removed from the large vault and transported in
smaller units that fit into a van.)
An obvious disadvantage of the neuro option is bad PR; it sounds gruesome.
Also, one would think that revival (as a whole, functioning, healthy human
being) when only your head was preserved would be more difficult than if your
entire body was preserved. However, the whole body situation may not be that
much better. Mike Darwin of Alcor noticed several years ago, when examing two
suspended people being transferred from another organization to Alcor, that
every organ of their bodies suffers cracking from thermal stress during
freezing. In particular, the spinal cords suffered several fractures. Thus,
the whole bodies were not quite as "whole" as most people assumed. Another
reason that a whole body may not offer much more than the head alone is that
the technology required to revive people from (whole or neuro) cryonic
suspension should also be able to clone bodies, which is much simpler than
fixing damaged cells. One possible objection to this approach of recloning a
body to attach to the head was voiced by Paul Segal of ACS (in the April 1988
issue of The Immortalist). He suggested that adult cells in the head may be
missing some of the DNA needed to reclone the remainder of the body. Even if
this objection is valid, it is easy to circumvent by storing samples of all the
major organs with the preserved head (which is standard practice at Alcor).
Alcor may soon offer a head-and-body option in addition to whole body and
neuro. The intention of this option is to achieve some of the advantages of
both the whole body and neuro options.
Freezing the Brain Only in Liquid Nitrogen
------------------------------------------
Steve Singley has published articles in the July 1988 issue of The Immortalist
and the Winter 1988 and Spring 1988 issues of Venturist Voice proposing brain
banking as a cheap alternative to full-blown cryonics. He points out that
brain banking more neatly falls under the organ donation laws than (whole body
or even neuro) cryonics and also suggests that brain banking is not perceived
as gruesome as head only (neuro) preservation and would thus be more publicly
acceptable. The major technical disadvantage of brain rather than head
preservation is that brains are fragile and easily torn; it is better to keep
them in the "factory-installed" packaging so that they do not get damaged.
Vitrifying Rather than Freezing the Whole Body, Head, or Brain
--------------------------------------------------------------
The cover article of the Aug. 29, 1987 issue of Science News describes
vitrification, which achieves cooling to a glassy state without the water
crystallizing into ice. The advantage of this is that the cells do not suffer
the mechanical damage from the crystallization. The main disadvantage is that
the concentration of cryoprotectants required to achieve this is toxic. It is
also, currently, a technically difficult and expensive process requiring
computer control of cooling rates, perfusion, etc. The March, 1988 issue of
Cryonics magazine ("The Future of Medicine", Part 2 of 2) suggests that
vitrification may not be needed for ordinary organ banking, since other, cheaper
methods may be good enough. For tissues and cells, though, it has a lot of
promise for the commercial market. Thus, commercial research into vitrification
may stop short of what is needed for making it viable for preservation of large
organs or whole bodies required by cryonicists.
Dehydrating Rather than Freezing the Whole Body, Head, or Brain
---------------------------------------------------------------
The cover article of the Feb. 13, 1988 issue of Science News describes some
microorganisms that survive dessication by forming hydrogen bonds between the
cell membranes and sugars such as trehalose. These microorganisms automatically
come back to life when you add water! Also, the Aug. 29, 1987 Science News
article on vitrification mentioned a combination of vitrification and freeze-
drying enabling room temperature storage of single cells. Freeze-drying whole
organs (or bodies) would be much more difficult and time-consuming, though, so
it's not clear that this approach will ever be a useful alternative to cryonic
suspension.
Downloading the Information in the Brain Into an Electronic Medium
------------------------------------------------------------------
Downloaders are people who want to download the information in their brains
to an electronic medium that can simulate the processes in their brains.
From what I understand of it, the main disadvantage of this approach is that
the technology to achieve it does not (yet) exist. Robert Ettinger (in the
July 1988 issue of The Immortalist) is less optimistic. He doesn't see how an
electronic instantiation of a person could be conscious.
Conceptually, downloaders sound to me to be just one step farther along the
progression from "vitalism" (life is forever mysterious and beyond mere matter
and mechanical things) to "informationism" (everything important can be
expressed as information transfer, generation, or storage):
noncryonicists -> cryonicists -> neuro -> downloaders
Does anyone have references to articles or books on downloaders? In particular,
what does Hans Moravec (of Carnegie-Mellon University) have to say on this?
- Kevin Q. Brown
...{att|clyde|cuae2}!ho4cad!kqb
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