IUBio

Modelling the human brain by modelling its evolutionary emergence

Frans van der Walle fw.novoware at wxs.nl
Thu Feb 21 18:23:14 EST 2002


mat <mats_trash at hotmail.com>
43525ce3.0202211153.4fa01eac at posting.google.com...
wrote:
> Forgive me if I am being obtusely stupid here but if in your
> 'modelling procedure' you are going to evolve the brain from a single
> or low-number cellular organism then your evolutionary 'protocols' or
> 'rules' will either be based at the cellular or subcellular (perhaps)
> genetic level? Further you say that to avoid the nullifying
> complication of having to know all the environmental variables since
> that time billions of years ago to now, you are going to 'aim' the
> evolution model at the current brain.  Now as I see it this raises
> three problems:
>
> Firstly - How do you direct evolution?  The whole essence of the
> modelling is to understand how chaotic/random variation led to the
> present state, aiming it means you eliminate the ability to gain
> knowledge about this.
>
> Secondly if you are going to model at a cellular or sub-cellular
> level, then you will need aiming information of the same resolution,
> which means you would have to know how the brain works at the cellular
> or even subcellular level before you started, rendering the project
> pointless as you would have already achieved what you want.
>
> Thirdly - You seem to want to understand aspects of cognitive function
> through this modelling procedure, but you are modelling at the
> cellular level.  Even if you could artifically evolve a brain, why do
> you assume that would give you any insight into how it gives rise to
> mind?  Why do you assume that the reasonably arbitrary distinctions we
> make of our mental function map in anyway isomorphically to functional
> mechanisms within the brain?  Evolution works at the genetic level,
> even if you modelled all the innumberable mutations since single cell
> organisms to the human genome, why would that give you any idea of how
> the brain works?  We have the genome now, it doesn't explain the
> brain.
>
> Shorten your posts.
************************************
My reply is as follows:

You are certainly not stupid, but you did know that already. I will try to
keep it as short as
possible. Your first problem could be answered as follows:
1  Evolution is not entirely chaotic. There is an ordering principle
involved as well, namely
   the selection criterion 'Survival of the Fittest'
2  A major modelling problem is therefore: 'What is the result of this
ordering principle for
   the build-up procedure for the 'life form design', as it will become
stored in DNA?
3  This, very important, aspect is discussed at length in chapter 1 of
'Biography of Man'.
   Below I will try to sketch a very short summary.
4  The test in the (hostile) environment, i.e. the struggle for life, will
determine whether or
   not any adaptation is favourable for that survival. This aspect must
furnish the unifying
   concept that will transform the results of the successful trials of the
tinkering procedure of
   evolution into a ‘neat' information handling architecture.
5  The evolutionary analyses show that the evolutionary tinkerer made, via
the survival test,
   successive adaptations in the transformation of sensory observations into
motor acts,
   leading to a continuous improvement, at least for successful adaptations,
in some virtual
   image, created in the brain, that 'mirrored' the observed environment and
the
   individual's, and other's, position and (intended) actions in that
environment. This is the
   major, in fact the only, 'design strategy' of evolution.
6  This gradually improved ‘mirroring' of outside reality in some
representation/image in the
   brain is an absolute necessity for coping in a favourable way with any
challenge that the
   environment may pose to the individual. It is therefore no wonder that
evolution's ‘trial
   and error' resulted in such a virtual image representation.
7  This virtual image is shown to have evolved, in successive life forms,
from simple, reflex-
   like, structures, via separate egocentric- and allocentric images into a
viewpoint
   independent true virtual image, that became in Homo sapiens and, later,
in Homo sapiens
   sapiens further extended into purely abstract representations, that have
lost any direct
   relationship with material outside reality, but nevertheless were
extremely important for
   survival via tool use conceptions, planning, foresight, recalls from
expanding know-how-
   and experience databases, etc.
8  The successfullness of these adaptations is judged by the primary
selection criterion in
   evolution:

'Does the modification/extension result in less fertile offspring?'

   If yes, the modification will disappear; otherwise it will remain and
contribute to the
   multiple variations in life forms, and if successful, will become even
dominant. It results
   in the evolutionary arbitration strategy that:
   8a  gives, in general, preference to social instinct norms above
individual instincts (care
       for the individual), at least within the individual's social group
(take primarily care of
       the weaker members of the social group, such as children, older and
handicapped),
       and:
   8b  avoids, if possible, unnecessary deadly (dangerous) struggle.
   This strategy promotes the number of fertile offspring.
9  These observations justify the statement that evolution constructed not
only some
   hierarchic structure but applied that structure also to one well-defined
information entity,
   the virtual image and the response to the challenge(s) it contained. The
struggle for
   survival ensured that this information entity, and the resulting
response, retained its well-
   defined character as a gradually improving 'mirroring' of outside reality
and of the
   individual's, and other's, position in that environment.
10 The same struggle for survival ensured that the response to the
challenges, as comprised in
   the virtual image, were also favourable for that survival.
11 We found further that this virtual image was gradually built up by
evolution via a strict
   'top-down' procedure. I discussed this already in a preceding
communication.

Your second problem does not exist, as far as I can see. The modelling
involves the gradual
upgrading of the virtual image in successive life forms and an analysis,
with several,
unavoidably somewhat speculative, assumptions, on the implementation of that
virtual imagein the neural structure. We keep away from (sub)cellular
levels; information handling is the
primary issue. In this aspect of the modelling procedure we make use of the
various available
'aiming points', as these can be derived, not only from Homo sapiens sapiens
but also from
much older life forms. A publication like that of Winson, 1990; 'The meaning
of dreams';
Scientific American November 1990 pages 42 through 48; See also: Scientific
American,
volume 276, special issue, 1997, pages 58 through 67, has played an
important role in this
'aiming procedure'. We found that this gradual neural implementation
procedure can also be
characterized by a hierarchic and recursive development procedure. As a
result, the immense
complexity of the brain becomes much easier to describe and understand. It
is (afterwards) no
wonder that evolution concluded that the neural emergence procedure should
be a simple
recursive process; seen from a control viewpoint for this 'design
information' handling task, it
could not have been differently. The resulting brain emergence process is
described in detail
in chapter 5 of 'Biography of Man', the 'aiming points' in section 5/3; the
neural
implementation in section 5/4.

Your third problem is, I think, resolved, or at least answered, already by
the above
observations. The resulting modelling is in fact the additional info, that
is at present lacking in
the genome project. After all, the genome project has discovered the
existence of a very big
book, written in 3 character words (the triplets), each built up from only
four different
characters (A, C, T, G) and written in a language we do not know. It is a
very difficult version
of the 'Rosetta Stone Problem'. The resulting modelling can be seen as a
first step in
unravelling the language problem for that Rosetta Stone.

I hope I have kept it sufficiently short. I look forward to further critical
comments and I thank
you for the stimulating discussion.
Regards,
Frans van der Walle





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