X-Message-Number: 868 Date: Sun, 31 May 92 23:48:37 +0200 From: (David Stodolsky) Subject: CRYONICS: Re: Brain Scan Question Thomas, I tend to agree that cryonic suspension is the best identity preservation option today. This is because it is the only one that has been subjected to a serious research effort. However, you say: >I have no doubt that someday it will be >possible to store a sufficiently complete description of a person so that >they can be recovered (including their identity) A major problem in getting that description is the damage caused by freezing. Is there any other way to preserve brain structure? Then the description could be written out using current known techniques and the ability to recover the person would eventually become available. I think we are underestimating what will be practical with future technology. I see no reason to believe that in the future, it will be either necessary or desirable to restart a suspended brain. Our knowledge today compared to that of the future could be like the knowledge the ancient embalmers of Egypt compared to that of today. With today's techniques, DNA from Egyptian mummies has been recovered from their bones and we could potentially clone one of these ancient kings. Unfortunately, the embalmers thought that the intestines were the seat of the soul, and while they took them out and preserved them, they discarded the brain. DNA was obviously well beyond their comprehension, but in attempting to preserve the body structure they also accidentally preserved some of this information. Perhaps our ideas of restarting a suspended brain will be seen in the future, just as we now look upon the idea of a mummified body being able to live again. Identity reconstruction is impossible with these mummies, because some of the steps taken to preserve them, given the technology of the time, were actually quite destructive. If we assume that brain (and DNA) structure is an adequate description of the person, then the structure preservation, without regard to its affect on reanimation is what we may wish to optimize. Then the brain is scanned (and this could take a hundred years) and the description is either stored in some very stable format, or immediately regenerated. We can assume the scanning ability will be available within 40 years. And it real doesn't matter how long the regeneration ability takes to develope (unless you are in a rush to get back). The overall probability of this path working could be greater then straight cryonic suspension, where you depend upon the continuous and reliable function of a organization (in a society) that will keep the LN flowing for hundreds of years, not to mention freezing damage. Chemical fixation and internment in permafrost is the closest thing we have to this now. It is also attractive because it is low cost and would increase participation, a political plus. With sufficient research this option could be made a lot more medically plausible. From the social standpoint it has some advantages. Current thinking tries to maximize preservation of subcellular structure, at some expense to macrostructure of the brain. If macrostructure (connectivity) is the basis of memory, then maybe we ought to change our priorities. Certainly, as individuals we have to choose what option is best for us at a given moment. But, my argument is that life extension research should not be locked into a single technology. Both cryonics and scanning have significant elements of hand-waving at the moment. With cryonics it is, "then we use the nano-machines." With scanning it is, "then we regenerate the memory structures in the cloned/simulated brain." If personality reconstructions is the goal, it is by no means obvious which of these is most likely to succeed in the future. More important, these methods could be used together to get a better overall result and this needs exploration. David S. Stodolsky Messages: + 45 46 75 77 11 x 24 41 Department of Computer Science Tel: + 45 31 95 92 82 Bldg. 20.1, Roskilde University Center Internet: Post Box 260, DK-4000 Roskilde, Denmark Fax: + 45 46 75 42 01 Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=868