IUBio

Modelling the human brain by modelling its evolutionary emergence

Frans van der Walle fw.novoware at wxs.nl
Tue Feb 26 06:09:24 EST 2002


Frans van der Walle <fw.novoware at wxs.nl wrote in berichtnieuws
a586jl$m8u$1 at reader08.wxs.nl...
> This message is a combined version of the my statements in preceding
> discussions; it is intended as a conclusion of my request for comment. I
> will address it as well to other bionet newsgroups. Many thanks for the
> responses obtained sofar. etc
**********************
I got following comment from Peter Brawley; I include below my respone
between ********:

Thanks. A few comments . . .
1. Even after working out most of the details regarding the universals of
matter and energy (eg, f=dp/dt, Maxwell's equations, e=mc², Planck's h,
quarks, &c), and nearly half a century after Einstein's death, physics
cannot formulate a unifying theory which works. Making such a theory is
difficult even for fairly simply and non-hierarchical processes. Arguably
neurobiology negins with a much harder problem, and obviously it has not yet
had its Einstein, or even its Newton & Maxwell -- it has no analogue to
f=dp/dt, no analogue to e=mc², &c, so compared with physics, it's in the
seventeenth century!
************
It is getting time we change that! My modelling is an effort to initiate
that; there were many (smaller) scientists who preceded Newton! I have not
the illusion that my approach is the final answer.
************

Now what's the likelihood that a general theory of the nervous system,
formulated on the basis of so little solid understanding, will turn out to
be substantially correct? Vanishingly small. So I would have thought that
the best result one could reasonably expect from such a project would be
hermeneutic, and that, for the next few decades, we will get much more bang
from smaller-scale analyses (eg Hubel & Wiesel on vision, the hippocampus
and memory, basal ganglia and action, &c).
************
I disagree, we have concentrated already too long on detailed aspects; one
does not see the forest anymore through the trees.
Patricia Churchland (1988) stated it very correctly in her book
'Neurophilosophy':
  ' our present day knowledge of the functioning of the human brain and mind
demonstrates clearly  the lack of some unifying theory for the information
handling processes in the human brain and mind.'

A similar statement, be it within another context, was made already in the
1930's by Vygotsky
(1934/1986):
  'The atomistic and functional modes of analyses prevalent during the past
decade (1934) treated
  psychic processes in isolation. Methods of research were developed and
perfected with a view to
  studying separate functions, while their interdependence and their
organization in the structure of
  consciousness as a whole remained outside the field of investigation.'
  'There are so many psychologies precisely because there is no one
psychology'.
These very early remarks are still valid according to me and should spur us
to a somewhat different aproach than the usual one.
**************

2. If the human genome project has shown anything, it's that DNA is not the
full specification for building an organism. The diff between a fruitfly & a
human is just 15K genes? Don't think so. Much info is encoded, then, in
processes which we don't as yet know anything about. So it's an error to
hang any design argument on DNA alone.
*****************
The human genome program considers only that part of DNA that codes for
proteins. It is only a (small) part of DNA; much more is 'hidden' in it,
often (I think inappropriately) identified as 'junk DNA'. There is just no
other genetic 'transportation vehicle' to the next generation.
****************

3. It's been a few years since I looked in detail at cortical studies, but I
am surprised by your confident summary of general cortical column
properties. Don't columns vary widely amongst areas? And the "chopping time"
is tendentious too, isn't it?
**************
No the cortex is remarkably constant, even between various mammal lines
(rats are often studied). The major exception is the visual cortex, but even
there it is only the neuron density that is some 2.5 times larger. See
further my reply to Matt Jones
The 'chopping time' assumption / postulate has a reasonably solid foundation
in experimental results of Singer and several others. (See my list of
questions in my communication of 23-02-2002)
**********
4. The assertion that "modelling of the present brain is only possible by
modelling its evolutionary
emergence" seems to me as absurd as it would be for the heart, or spleen..
***************
See my reply to Matt Jones of today (26-02-2002).
*************
5. Whatever reason is there to imagine that 'conscious' and 'unconscious'
brain networks (a) exist and (b) are separate!?
**************
In my modelling these are interconnected networks; in fact it is only one
network. However, the evolutionary analyses lead to the assumption /
conclusion / postulate that one segement is created by a different recursive
procedure, making it into the hidden layers = nodal points of a feed
forward/backward network; it is part of conscious 'seeing/feeling/hearing'.
The other segment interconnects the hidden layers via a different recursive
procedure and operates, I assume/postulate/conclude, unconsciously. It
models/explains the phenomenon of 'sudden revelations', 'AHA Erlebniss',
Serendipity, etc. Any information transformartion in the second network
segment will, ultimately, 'arrive' in another nodal point, leading to such a
conscious revelation. Note: The sole modelling test is: Is it isomorph with
reality? It explains therefore at least an important part of Man's
functioning.
***********

6. To refer to memory & learning as primarily 'storage' is a fundamental
error.
**************
I don't understand your remark. Of course recall is also part of it and,
most importantly, abstracting and prototyping.  What we did find is that Man
does not truly 'invent' something really new; it is all based on information
scanned in the environment and as received from others by their
communications. We are all symbionts / parasites, I am afraid! Real
procedural analysis is a conclusion after the event. We are less original
than we think! You will find this statement in many places, but we hesitate
to accept our 'lower standing'. Robots will, ulimately after a long further
development, become brighter than we are! Only we will not be there anymore;
our grandchildren will have to solve that ethical puzzle!
************
There are so many problems to solve in neurobiology; most of them must be
solved before anything like a unified theory or model would be even
intelligible, much less testable. I hope you decide to apply your
considerable energies to one of those more modest problems.
************
See my response above, quoting Churchland and Vygotsky.
*******
P.
Many thanks for your remarks
Frans van der Walle





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