Re: A non-destructive brain scan for uploading?

Anders Sandberg (
Mon, 17 Mar 1997 16:01:46 +0100 (MET)

On Sun, 16 Mar 1997, Robert Schrader wrote:

> An intriguing thought. Thanks for posting it.

I agree, this is a new idea (I think). I see some problems with how to
use it though: using some form of fast holography (since we need the 3D
data) we only get optical information at a certain wavelength: how do we
tell apart the different chemical states that are important for brain
structure and function (like what neurotransmittor a given synapse uses
or what state of LTP it is in) using optical information? Knowing the
what the hardware looks like might help us deduce the internal
properties, but this is likely to be highly nontrivial since it is hard
enough to distinguish one cell from another using visible light. In order
to get enough resolution we might need to go into the UV, and then we
start having trouble with energy densities anyway.

> If it works, we have structure but not state. In light of recent posts
> about individual neurons storing info, determining the state of all
> the neurons may be neccesary also.

Neural state is probably not important to achieve uploading, since
personhood is apparently well preserved in saved drowning victims in
northern rivers; for a while their neurons are completely inactive due to
cooling, so their dynamic states are most likely lost. They emerge from
the ordeal with a brief retogerade amnesia (apparently briefer than the
amnesia of people with medial temporal lobe damage, suggesting that LTP
in the hippocampus is preserved) but otherwise with no disruptions of
self-hood (if the anoxia was not too severe, of course).

If you want to upload yourself with perfect continuity, so that the
transition is done in a conscious state, then you need to take neural
states into account. But for a plain uploading, all you need to deal with
is neural topology, chemistry and perhaps LTP state (+ similar things).

Anders Sandberg Towards Ascension!
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y