X-Message-Number: 12207 From: Thomas Donaldson <> Subject: once more, a REPEAT about brain versus head preservation Date: Thu, 29 Jul 1999 00:24:34 +1000 (EST) To all those discussing brain preservation (as distinct from heads): Unfortunately the process of cryonic suspension involves infusing the brain (or head) with cryoprotectant solutions, which replace the blood. And given the way that brains receive their blood (from the outside in rather than from the inside out, as kidneys do) it becomes surgically very difficult to remove a brain from the head without damage. That difficulty becomes even more because brains have no "stiffness": a living (or recently "dead") brain does not hold together very well at all. After all, that's just what our skull is for. It may make sense to describe head preservation as brain preservation, but to take that literally gets into lots of hard technical problems. You may agree or disagree with head preservation, but right now it seems to be the only practical way to preserve brains. Best and long long life for all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=12207