From: tsf+@cs.cmu.edu (Timothy Freeman)
Newsgroups: sci.cryonics,news.answers
Subject: Cryonics FAQ 5: Neurosuspension
Summary: This posting contains a list of Frequently Asked Questions
   and their answers about cryonics, the practice of carefully preserving
   very recently clinically and legally dead people in hopes that they can be
   revived in the future.  It should be read
Date: 1 Jan 93 08:36:40 GMT
Article-I.D.: cs.part5_725877379
Expires: Sun, 14 Feb 1993 08:36:19 GMT
Followup-To: sci.cryonics
Organization: School of Computer Science, Carnegie Mellon
Supersedes: <part5_723198982@cs.cmu.edu>

Archive-name: cryonics-faq/part5

		      Section 5: Neurosuspension

(You can fetch cryomsg "n" by sending mail to kqb@whscad1.att.com or
to kevin.q.brown@att.com with the subject line "CRYOMSG n".  The index
to this FAQ list is cryomsg "0018.1".)

5-1.  What are the pros and cons of neurosuspension (only freezing the head)?

(The next two paragraphs are taken from CRYOMSG 6.)

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).

If the technology for suspension improves enough to make it
possible to store a body without much damage, that might tilt the
ideal tradeoff away from neurosuspension if the stored body is easily
repairable. 

See the booklet "Neuropreservation: Advantages and Disadvantages"
published by Alcor for a more thorough discussion.

5-2.  How many people have chosen neurosuspension over whole-body
      suspension? (This question has only a partial answer.)

The different organizations market neurosuspension differently, so
the answer depends on which organization you have in mind.  

>>>Question sent to alcor@cup.portal.com on Wed Jul 29 1992<<<

As of June 20, 1992, Alcor had 271 suspension members and 22
members in suspension.  I don't yet have information about how
many of the suspension members have chose neuropreservation.

ACS has six whole bodies, two heads, and two brains in cryonic
suspension.  They can do neurosuspensions, but they do not promote the
option.  Art Quaife estimates that less than 20% of the living
members of ACS have chosen neuropreservation.

The Cryonics Institute does not do neurosuspensions.
Newsgroups: sci.cryonics