Re: Science News: Memory impairment not due to lost neurons

Christopher Heward (
Mon, 23 Sep 1996 22:12:57 -0700

You wrote:
>Browsing Science News over my morning coffee, I found an encouraging report:
>The old idea that memory impairment in older people results from the loss of
>neurons in the hippocampus has been challenged by a couple of recent studies.
>Instead of looking at a thin slice of rat hippocampus, researchers counted
>neurons in 3D pieces. They found no evidence that the older rats with memory
>impairment had fewer neurons. Though this study needs to be done on human
>hippocampuses, this gives reason to think that memory impairment results
>from changes in function of neurons (making different proteins, etc.) rather
>than in neuronal loss. That's good, because it should make preservation and
>restoration of function easier.

I read the same article and got a different hit. If memory loss results from
subtle changes in neuronal function, then perhaps invisible and irreparable
damage is done during cryonic suspension. Furthermore, it is often
more difficult to prevent and/or correct subtle damage to cells and tissues
than it is to prevent and/or correct gross damage or death. Brain cells that
look normal anatomically may not function normally and important i
nformation (memories) may be lost. Thus, the report in Science News is not
necessarily good news for cryonics.