X-Message-Number: 20039 Date: Fri, 13 Sep 2002 08:46:44 -0400 From: Thomas Donaldson <> Subject: CryoNet #20034 - #20036 For James Swayze: Unfortunately or not, I was not referring to any holographic theory of memory, nor is that the common view of how memory works. Basically (so the common view says) our memories are encoded by the existence of connections between particular neurons. That is, a particular memory consists of a set of such connections; it may be itself spread among many neurons, with each holding a part of it, but depending on just what it is a memory of, destruction of some of these connections would destroy the memory. In a way, neuroscientists have gone back to an older theory which located abilities and memories in particular regions of the brain; it's much more complex and sophisticated now than that older theory, but in one way it's in the same family. Some neuroscientists actually have proposed that particular memories are stored in just one neuron, though most would not go so far. (Actual memories are quite complex, as anyone who does any introspection will see). To be blunt, most neuroscientists would now think Kurzweil was WRONG. There was a period in the 60's and early 70's when some thought that memories were stored in chemicals which spread widely through our brains. This theory has now been disproven, but it may be the theory which led Kurzweil to make his statement. As I said at the end of my discussion, one major thing I have been doing in my newsletter PERIASTRON is considering experiments on both memory and identity. If our neurons really do remain static and with fixed connections for our whole life (like computer memories) then any attempt to revive someone from freezing (as distinct from vitrification) would require tracing out and rejoining all those broken connections caused by freezing. That's not impossible if we look in detail at how brains are put together, but full abilities to do that may take some time. However there is also evidence that our connections do not remain static over our lifetime, which raises questions about this whole theory of memory. Even growth of new neurons and replacement of old ones by new ones raises such questions. So I do not think that the most common present theory of memory will keep its present leading position for much longer, but can't yet make a reasonable guess about what will take its place. Someday I will discuss what neuroscientists have thought about identity, too. As for both memory and identity, I would definitely say that it helps to learn about what others have thought on those subjects, if only because doing so will help you avoid mistakes which causes them to adjust their theories. To theorize about such things without doing some reading beforehand risks that you come up with a theory that those who have been at it longer than you have ALREADY found to have many faults, enough to exclude it....and to be more general, the way to come up with an original idea isn't to ignore what others have said but to pay attention to it and work out a new way to get around its problems. Best wishes and long long life for all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=20039