Freeman's book

[From Bill Powers (950519.1325 MDT)]

John Anderson (950519.1045) --

     Here's a blurb about Walter Freeman's new book that sounds quite

Since you've read the book, I'd like to ask a few questions.

     While individual human brains are capable of truly remarkable feats
     of logic and technical virtuosity, which are the goals of emulation
     in artificial intelligence, they have evolved primarily as organs
     of social cooperation and understanding.

How does Freeman know that?

     These constructions are done by dynamical brain processes that are
     pre-rational, pre-logical, and non-computational.

Doesn't this depend a lot on what you mean by "computational?" How does
Freman define it?

     Recent studies of nonlinear brain dynamics during animal behavior
     have shown that perception does not consist of information
     reception, processing, storage, and recall. It is the creation of

How did they show that? What does Freeman mean by "meaning?"

     However, for social bonding to occur, which leads to the emergence
     of shared meanings in respect to scientific principles, and to
     shared values in respect to aesthetics, one or more forms of
     'unlearning' is required, by which already learned value systems in
     individuals are dissolved, and new ones are learned in their place,
     through socially cooperative actions.

How does he know that?

     Recent studies of brain chemistry in animals during reproductive
     behavior have revealed the operations of neurohumoral mechanisms,
     which have evolved to promote success in mammalian reproduction and
     the care of altricial young.

"Altricial" is not in my dictionary. What does it mean? How did Freeman
find out that these neurohumoral mechanisms have evolved to promote
success in mammalian reproduction and the care of "altricial" young?

     I believe that our remote ancestors learned to adapt these chemical
     mechanisms to re-shaping the synaptic networks in their brains.

Why does he believe that?

     In essence, they learned to form pair bonds and tribal groups by
     means of music, dance, and sexually based rituals surrounding the
     use of totems and icons, which have further evolved into our
     present techniques and circumstances for religious and political
     conversions, and the most effective forms of scientific and
     artistic education.

How does he know those things?

The reviewer says

     In this essay written for the occasion of the Spinoza lectures of
     the University of Amsterdam, Walter Freeman introduces the new
     concept of neuroactivity which is defined as the structure of brain
     operations that forms the interface between the electrochemical
     signs of neuronal populations and overt measured behaviors.

How does that structure of brain operations form that interface?
couldn't almost any model of brain operation fit that definition of

     The pivotal concept of neuroactivity is that to understand brain
     functions it is essential to take into account the dynamics of
     neuronal populations and not just the behavior of single neurons.

Is this supposed to be a new idea?

     Intrinsic to Freeman s analysis of the signals generated by the
     neuronal networks of the brain (i.e. EEGs) is his conviction that
     within the apparent unreproducibility and unpredictability of EEG
     signals there may be a hidden chaotic determinism, although he
     admits the difficulties in measuring chaos in such brain signals.

Is Freeman claiming that because he can't predict or reproduce brain
waves, they are inherely unpredictable, unreproducible, and chaotic?



From you:

     Has anyone tried to construct a PCT model of Parkinson's disease?
     I'm thinking of proposing to do this in the grant I'm working on.
     I'd appreciate any info.

What is it about Parkinson's disease that you want to model? The
oscillations are fairly simple to reproduce; just set the parameters of
the model so it begins to oscillate. This, of course, only hints that
the symptoms result from changes in control parameters; it doesn't tell
us anything about what is causing those changes.

Bill P.