X-Message-Number: 902 Date: 13 Jun 92 20:56:26 EDT From: Thomas Donaldson <> Subject: Re: Macro-Damage Hi to all! After thinking about it I have a bit more to say about Steve Harris's message. Right now, cryonics and cryonicists can't claim to have any understand- ing of memory and how it works --- particularly the very long term kind that we basically want to preserve on our suspensions. Certainly it's true that lots of destructive events happen in brains that may have been left lying about in the open for several days. ON THE OTHER HAND, until and unless we fully understand not only how memory works, but how CLUES to it may be derived, it remains unclear that even in such extreme cases a person's memory has been destroyed. By "clues", for instance, I mean such things as preservation of DNA together with whatever switches cause particular genes to be turned on or off (the existence of a connection between 2 neurons may not have been preserved, but it may be possible to work out that they must have been connected by using such information. Don't get me wrong. If we don't understand just what structures encode or preserve our memories, then the less damage the better --- since the less damage there is, the less likely it is that clues to memory have been destroyed. However I think that the very strongest thing that medicine or science can say, RIGHT NOW, about the revivability of people like Michael Friedman is that we don't know enough to tell. (For someone frozen in better conditions, chances again look better, but we still don't know). I would finally point out that some empirical work might clarify a few of these things ... not that trying to freeze someone in good condition shouldn't take priority. But simply by trying to take slides of brains after 24 or 48 hours we might get a firmer idea of their condition. And after all, brains don't just turn into soup under those conditions, so SOME structure must survive. The question is how much, of course! Best, Thomas Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=902