X-Message-Number: 18159
Date: Fri, 14 Dec 2001 17:15:35 -0800
From: Dave Shipman <>
Subject: Should we preserve the body too?
Friends,
Carole Eklund (#18142) asked a few simple questions, to which Robert
Ettinger (#18144) responded with some simple answers. I suspect simple
answers are what Carole really wanted. But the issues raised are much more
complicated, especially the question of whether the rest of the body should
be preserved along with the brain. Cryonics Institute only does whole-body
suspensions in any case. Alcor has traditionally done both whole-body and
neuro (just the head) suspensions. But Alcor now uses the new vitrification
procedure for cryopreservation and currently this only works for neuro
suspensions. Since vitrification is so superior to the previous suspension
methods, and since preservation of the brain is seen as critical, the
tradeoff now preferred by Alcor is head-only vitrification instead of
whole-body suspension using the older cryopreservatives.
Of course, this raises the question of how do you get your body back if
only your head is preserved? The assumption is that it will be possible to
clone a new body from your DNA and attach your preserved head onto that.
The clone would be grown without a head. Since the brain is "the seat of
the soul", the headless clone would not be a conscious thinking feeling
being. There really shouldn't be any moral or ethical issues involved here.
Still, much of the general public would find the whole idea ghoulish in the
extreme. Perhaps it would be less objectionable if the new body were
regenerated outward from the head, in the way a lizard grows a new tail. In
the future, this won't seem so strange. We are already doing research on
regenerating arms or legs that have been lost. Now we are just talking
about regrowing a new body from the head. Since there is no possibility of
a separate "person" (the clone) being created only to be sacrificed, this
approach may be more easily accepted.
It seems a safe bet to assume that one way or another a new body can be
created for your head. Nonetheless, I think there are several reasons why
the body should be preserved too. Here are some that concern me, surely
there are others. (Below I assume the "headless clone" solution, but
similar problems exist under the regeneration scenario.)
1) The brain and the body co-developed together. The neural structures
in the brain reflect the structure and detailed anatomy and physiology of
the particular body it grew up with. The DNA at best only specifies the
gross outlines of body structure. It does not specify in detail exactly
where every single nerve, blood vessel, muscle fiber, endocrine vesicle,
etc., is located and the details of how they are arranged and interact.
These details are determined during development and continue to be modified
throughout life. And the brain, which monitors and controls these body
structures, developed at the same time along with these structures. In
other words, the detailed brain anatomy and physiology matches the detailed
body anatomy and physiology like a hand in a glove. If a new body were
cloned, even from the same DNA, there would be a mismatch between the new
body and the old brain. It is unclear whether this would be a serious and
fatal mismatch or if the mismatch could be corrected, either by normal
adaptation of brain structures or perhaps by some sort of physical therapy.
But remember, we are not just talking about control of skeletal muscles but
internal physiological processes such as digestion, heart function, hormone
levels, and on and on. We want all these to work and it isn't obvious to me
that my old brain, which developed to monitor and control my old body, will
be able to monitor and control my new body, at least not without a lot of
extraordinary medical technology which I don't hear anyone talking about or
even considering.
2) There are something like 13 million neural axons projecting through
the cervical vertebrae that must be reconnected. The spinal cord consists
of long axons, some as long as several feet, which are projections from
neuron cells in the brain. In other words, when the head is severed the
neuron cells themselves are being cut apart. The part of the cell remaining
in the old brain will have to be connected to the axon part of the cell in
the clone's spinal cord. A clone would necessarily consist of complete
cells. It seems that at least enough brain must be present in the clone to
supply the axons for the spinal cord. That is, at least the "body
interface" neurons of the brain must be present in the clone in order for
there to be a spinal cord at all, since the spinal cord consists of the
axons of these neurons. Now it is unlikely that the number of spinal
neurons in the clone is exactly the same as the number of spinal neurons in
the preserved brain, due to developmental considerations discussed above.
But even if there were exactly the same number of corresponding neurons,
the question remains, how do you connect them up? I have enormous faith in
future technology, but it seems like the problem would be much easier using
the old body. Even with a cloned body, having the old body available as a
reference would surely be helpful.
3) Important neural activity takes place outside the brain. For
example, much of the neural control of digestion takes place in neural
plexuses in the abdomen. I don't believe anything is going on here which
affects my identity, memories or sense of self. But since our understanding
of such issues is so primitive, it may be safer to keep all this stuff
around just in case it turns out that it really does matter after all.
So what is the cryonicist to do? Both CI and Alcor will do a whole-body
suspension if you like, but using the old cryopreservatives which do not
preserve the neural structures nearly as well as the vitrification
technique. But with the vitrification preservatives, only the head can be
cryonically suspended. Although Alcor does not advertise the fact, it is
possible to purchase two separate contracts, one for neuro-vitrification
and another for preservation of the rest of the body using the older
solutions. But this costs a whole lot more and the spinal cord is still
severed. Clearly the best approach is to push on with research in
whole-body vitrification. The problems are formidable, but I for one will
feel much more comfortable when the cryonics organizations are able to
provide a whole-body vitrification service.
-- Dave Shipman
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