X-Message-Number: 13403 Date: Sun, 19 Mar 2000 07:01:00 -0500 From: Thomas Donaldson <> Subject: CryoNet #13402 Hi everyone! This is for Bankston: I have felt the need to study brain injury and recovery from it, plus the processes which cause our memories, for years now. Although I myself may even count as someone injured in one of the ways you describe, that was never my motivation. Fundamentally, if we want to revive someone then we'll need not only to revive them with a working brain but also with a high percentage of their memories. It's the revival of memories which may prove hardest. There is already work, particularly with Parkinson's Disease but also some work with Alzheimer's (less successful) to transplant new neurons into injured brains. Like all such early work, it has hardly become guaranteed as successful enough to use on patients, but the basic methods for such repair already exist. It is also true that some brain areas, particularly the hippocampus but others also (particularly in the lower brain) may not hold any significant memories and thus could be replaced simply by transplanting new neurons appropriately guided (the hard problem --- but some abilities to guide neurons have already been developed). The discovery that we form new neurons in various places (such as the dentate gyrus of our hippocampus, and most recently the strong suggestion from work with primates that we may form new neurons in many higher brain locations) can obviously be tried as means to promote healing, too --- though I do not know of any groups which have yet done so. Current works mainly involves use of transplants. One major expression of memory seems to be the formation of new connections. Since these connections all take place on a scale currently too small to allow them to be seen easily and tested for their memory content, this does not immediately help us with the problem of reviving MEMORIES. However that problem can be got round in various ways. Finally there is a significant effort by some cryonicists to actually avoid this problem in the future completely, by finding a far less destructive method to preserve brains, and ultimately a method which allows complete reversibility. The key work here is "vitrification": finding a solution which makes the patient's brain not freeze but turn into a glassy substance. This work is having some significant success, which includes vitrification of large animal brains (no, they were not revived afterwards, but still showed far less damage than with normal freezing). I'd count myself among the relative optimists about such work, and have given money to help it. However I also believe that we're not only obligated to try to revive those suspended by older methods, but also that we can expect even some future suspensions to use more primitive methods, basically because the equipment and supplies for the most advanced suspensions happen not to be available when someone needs suspension. If you have not heard of references for the scientific work I describe, then I can give it to you separately. I also publish a newsletter specifically for cryonicists in which studies of how memory works and repair methods for nervous systems are described with references to the original articles. The discovery that primates make neurons in a widespread fashion is only a few months old, for instance, and that work is discussed fully in the newsletter --- named PERIASTRON. If you are interested in seeing what it's like, you can buy a one-issue subscription for $3.00 US, or alternatively buy N issues for $3.00 US X N. It comes out every other month, so a subscription for a year is $18.00 US. Best and long long life, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=13403