[ExI] Zombie glutamate

[John Clark]

On Sat, Feb 14, 2015 at 4:44 PM, <avant at sollegro.com> wrote:

> While Brent is not completely wrong because susbtrates do have very
> specific structures that enable their function, the structural
> considerations outweigh the simple identity of the substrate. For example
> a hemoglobin molecule denatured by heat would still chemically be
> hemoglobin, but it will have lost its delicate folded structure and
> thereby all of its biological function.
>

Denatured hemoglobin chemically reacts very differently than non-denatured
hemoglobin does, and the logical structure of a brain fed by denatured
hemoglobin would be quite different from your brain, the neurons would
respond to signals differently because they were dead, killed by lack of
oxygen. But if done competently they logical schematic of your uploaded
brain in a electronic computer would be identical to the logical schematic
of your biological brain.


> > If you want to simulate the mind, you would have to
> simulate the human brain from the atoms up along with any attendant
> chemistry and physics. You might even have to simulate the rest of the
> body as well, after all, I wouldn't feel quite like myself without my
> adrenal glands or my testicles subtly influencing my thinking.

I see nothing sacred in hormones, I don't see the slightest reason why they
or any neurotransmitter would be especially difficult to simulate through
computation, because chemical messengers are not a sign of sophisticated
design on nature's part, rather it's an example of Evolution's bungling. If
you need to inhibit a nearby neuron there are better ways of sending that
signal then launching a GABA molecule like a message in a bottle thrown
into the sea and waiting ages for it to diffuse to its random target.

I'm not interested in chemicals only the information they contain, I want
the information to get transmitted from cell to cell by the best method and
few would send smoke signals if they had a fiber optic cable.
The information content in each molecular message must be tiny, just a
few bits because only about 60 neurotransmitters such as
acetylcholine, norepinephrine and GABA are known, even if the true number
is 100 times greater (or a million times for that matter) the information
content of
each signal must be tiny. Also, for the long range stuff, exactly which
neuron receives the signal can not be specified because it relies on a
random process, diffusion. The fact that it's slow as molasses in February
does not add to its charm.

If your job is delivering packages and all the packages are very small and
your boss doesn't care who you give them to as long as it's on the correct
continent and you have until the next ice age to get the work done, then
you don't have a very difficult profession. I see no reason why simulating
that anachronism  would present the slightest difficulty. Artificial
neurons could be made to release neurotransmitters as inefficiently as
natural ones if anybody really wanted to, but it would be pointless when
there are much faster ways.

Electronics is inherently fast because its electrical signals are sent by
fast light electrons. The brain also uses some electrical signals, but it
doesn't use electrons, it uses ions to send signals, the most important are
chlorine and potassium. A chlorine ion is 65 thousand times as heavy as an
electron, a potassium ion is even heavier, if you want to talk about gap
junctions, the ions they use are millions of times more massive than
electrons. There is no way to get around it, according to the fundamental
laws of physics, something that has a large mass will be slow, very, very,
slow.

The great strength biology has over present day electronics is in the
ability of one neuron to make thousands of connections of various strengths
with other neurons. However, I see absolutely nothing in the fundamental
laws of physics that prevents nano machines from doing the same thing, or
better and MUCH faster.

  John K Clark
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20150216/94b33602/attachment.html>