[dorkbotdc-blabber] Bayesian theory of the brain in New Scientist

[Lorne Covington]

This looks like a repackaging of known concepts that really only applies
to perception.  It seems to be about modeling how the mind creates a
more correct internal representation of the external world at a low
level, not about how the mind does things with that information, much
less create novel thoughts.  Bayesian methods are certainly cool, used
them back in the '80s to deduce likely position and heading from
multiple nav sources with differing errors.

Let's say you see something in your peripheral vision.  Maybe it's
surprising, and you turn to look at it to get more information.  Maybe
it's not, compared to other mental and perceptual processes, and you
ignore it, probably without even knowing it.  So I don't see how
"reducing free energy" explains the mental processes going on that
decide whether or not to seek more information about that object versus
to continue eating, finishing that soldering job, or finding that
perfect phrase for your poem.

Certainly the fact that the cortex has feedback paths is no great news.
Others have gone farther to say those feedback connections also provide
the way for higher brain layers to model or synthesize sensory
experience, such as when you play or sing a tune in your mind, or
picture something in your mind's eye that you have never seen (a zorse,
say).  Don't see how Bayesian methods can do that.

Jeff Hawkins "On Intelligence" gives a pretty good overview of this type
of thing, but I think he tends to claim too much as his own insight.
Plus he's trying to patent it all.  He does have a cortex modeling kit
you can download for free for non-profit work, but be warned you'll sign
away a lot of future rights to get it (numenta.com).

So to answer the question posed by the blog, "is there a unified theory
of the brain?", the answer appears to me to be "no".  Of specific
perceptual processes, perhaps.

Thanks for the link, I will go read the source papers!

Cheers!

- Lorne

P.S. - Other books I've found fun: "Descartes' Error" by Antonio
Damasio, and "Sweet Dreams" by Daniel Dennett.


Alberto Gaitán wrote:
> On our topic of modeling creativity, here's an interesting take on 
> modeling the human brain as a Bayesian engine:
>
> http://reverendbayes.wordpress.com/2008/05/29/bayesian-theory-in-new-scientist/ 
>
>