Three years ago I posted Brain Storms - 2 - The Black Hole In Brain Research suggesting why there were problems in bridging the gap between the brain's neural network and human intelligence. Earlier this year both the E.U. and the U.S.A. announced multibillion pound projects to try and bulldoze a solution. P.Z. Myers has now posted a blog What are you going to simulate? on Pharyngula and I have posted the following comment, which may be lost among nearly 100 other comments on his site.
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The research seems to be working on the assumption that if we
knew all the connections we would automatically understand how the brain works and
what makes us different to animals. I would suggest that the best way to
understand how the brain works may well be to start at the animal end and
consider the possible evolutionary pathways. For this reason I agree with P.Z. when
he says
What the
hell? We aren’t even close to building such a thing for a fruit fly brain, and
you want to do that for an even more massive and poorly mapped structure?
Madness!” It turns out that I’m not the only one thinking this way: European scientists are exasperated with the project.
Of course this model is really crude in terms of formal
mathematical logic and does not even support the idea of an explicit NOT. Many
years ago the AI guru Minsky pointed out why, in mathematical terms, such
models were not logically powerful enough, but any ten year old who has been
taught about Venn diagrams could point out the flaws. So it would appear
obvious that research in this direction would be a waste of time. After all we
know we are ever so intelligent, and therefore there must be some kind of
philosopher’s stone of intelligence, possibly in the form of some special
genetic mutation, that makes our brain different to a primitive animal brain.
As far as I can determine everyone has assumed that our
marvellous human brain could not have such an appallingly crude driving
mechanism at the heart of it – and in making this assumption we have forgotten
how evolution can be very good at getting the best out of unpromising material.
As a result I am looking at how such a crude system might evolve into a human
brain.
An important resource in this process is the archive of
mainly unpublished research findings relating to an attempt to design a “white
box” information processing system to help the human user to handle
incompletely defined information processing tasks. The planned white box system
handled recursively defined associatively addressed set names in a bottom up
manner while the conventional “black box” computer is a top down rule based
system that processes numbers in a numerically addressed linear store. The research
showed that the approach was able to handle a wide range of non-numerical
tasks, including A.I. style problem solving, but for non-technical reasons the
work was abandoned over 25 years ago.
The original white box proposals included a number of
conventional computing type features, such as the ability to do arithmetic and
to drive a computer terminal, but if these frills are stripped off the inner
workings can be mapped onto the crude brain model. A comparison demonstrates
that such a simple approach could handle large quantities of poorly structured information
– could support at least a simple language, and even morph into something like
a programming language if required to handle complex sequential tasks.
Once it is realised that the primitive brain model can do
significant useful work a consideration of evolutionary pressures suggests that
there is a barrier to animals being more intelligent set by the amount of
useful information that can be learnt in a lifetime. However once a primitive
language becomes an efficient way of transferring reliable cultural information
between generations the barrier falls away, and cultural evolution takes off
like a rocket. As language is a tool that can be learnt and improved, the
language will rapidly become more powerful, allowing information to be
transferred even faster. A minor genetic change in the learning mechanism would
speed the process even more – but make it more likely that people would be more
inclined to follow charismatic leaders without question (i.e. religion?). In
addition it seems very likely that information learnt in abstract terms via
language would use the neural network more efficiently, increasing the brain’s
knowledge capacity with no increase in physical size. In modern humans the
cultural information serves to hide some of the limitations of the crude
internal workings – but some important human brain failings, such as
confirmation bias and unreliable long term memory, are predicted by the model.
Basically the model predicts that there is no major
difference between the way our brain works, and an animal’s brain works. The
difference is by using language we have greatly increased our rates of learning
and that what our intelligence is virtually entirely due to cultural knowledge.
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