Brain clues to attention disorder - AoK Ap9

k p Collins kpaulc at [----------]
Sun Dec 21 19:42:12 EST 2003

"k p Collins" <kpaulc@[----------]> wrote in message
news:d6qFb.4254$IM3.2778 at
> [...]

> For those who have it, see the discussion of "functional
> multiplexing" in AoK, Ap9 [There's also more important
> discussion of "inversion" there, too.]
> [...]

Here is AoK, Ap9:


    With  respect  to  the  primacy  of  the  TD E/I-minimization
    principle that  is asserted  by Duality  Theory, one question
    looms importantly.  If the  functioning of  the CNS  revolves
    tightly  around  TD  E/I  minimization,  then  why do so many
    different excitatory  and inhibitory  neurotransmitters exist
    within  it?  If  TD  E/I-minimization  is the only thing with
    which the biology of the central nervous system is concerned,
    then  wouldn't  just  two  [1] substances, one excitatory and
    one inhibitory, be adequate?

    Duality  Theory  holds   that  the  various   excitatory  and
    inhibitory neurotransmitter substances constitute a system of
    tuneable chemical "insulation". This set of things, which  is
    referred to as  "functional multiplexing" within  the theory,
    creates "selective  electricity" that  permits the  CNS to be
    wired  up  in  an  especially-compact  and efficient way. The
    various neurotransmitters allow portions of its circuitry  to
    be  used  redundantly   within  different  circuits   without
    creating  cross-circuit  interference.  This  has substantial
    advantages  which  include  the  elimination  of the need for
    entire  levels  of  supersystem  integration  circuitry,  the
    minimization of  CNS bulk,  the minimization  of neural fiber
    lengths with  an associated  reduction of  energy consumption
    and,   most-importantly,   the   minimization   of   response
    latencies.  These  things   greatly  enhance  an   organism's
    propensity  for  survival.  Thus,  within Duality Theory, the
    various transmitter substances constitute a "kit of tools" [2],
    albeit  a  substantial  one,  that  renders  the  global   TD
    E/I-minimization process more efficient.

    Duality Theory  holds that  neurochemical deficits  cannot be
    associated  with  single  behavioral  deficits. Rather, since
    neurotransmitters act as switch-junction building blocks, any
    particular  neurochemical  deficit  occurs  as  a  variety of
    partial behavioral deficits. Furthermore, spatially-separated
    occurrences of any neurotransmitter substance do not have any
    necessary behaviorally-relevant commonality which  supercedes
    that which exists within  the underlying neural topology.  If
    there  is  a  natural  "barrier"  (spatial,  glial,  and   at
    microscopic levels, active  breakdown and/or re-uptake)  that
    separates  neurotransmitter  locations,  then a neurochemical
    can be reused in a second circuit having a  function  that is
    independent  of   a  first   circuit  that   uses  the   same
    neurotransmitter.  Physical   separation  obviates   chemical
    (electrical) separation. [3] [4]

    [1] For background information see THE  BIOCHEMICAL  BASIS OF
    NEUROPHARMACOLOGY, by  J. R.  Cooper, F.  E. Bloom  and R. H.
    Roth, New York, 1982.]

    [2] The only way that it can be shown that the  neurotransmitters
    constitute more than such "tools"  is to show that they  undo
    the special topological homeomorphism  of the CNS so  that it
    no  longer  exists.  Otherwise,  the   relatively-specialized
    neurochemically-mediated dynamics must operate in  accordance
    with  the  reality  of  that  globally-integrated  structural

    [3] Therefore, Duality Theory holds that artificial (non-natural)
    applications of  neurochemical substances  which do  not take
    the microscopic and global realities of the underlying neural
    network into account cannot produce a fully functional global
    system. This, of course,  includes all applications of  drugs
    by any means  other than tissue  transplant, and even  in the
    case of tissue transplant, the degree to which the transplant
    is  able  to  replicate  the  naturally-occurring circuitry's
    macroscopic and microscopic topology limits the effectiveness
    of the transplant. These considerations are also impacted  by
    the  prior  "learning"  (microscopic  neuronal modifications)
    that the global system has experienced.

    [4] See "Transplantation in the Central Nervous System", by A.
    Fine,  SCIENTIFIC  AMERICAN,  Volume  255,  Number 2, August,
    1986, p. 52. This  article shows that tissue  transplants do,
    at least  to a  degree, reconstruct  portions of  the special
    topological  homeomorphism,  and,  thus,  are governed by it.
    This article  also discusses,  and depicts  diagrammatically,
    bilaterally-asymmetrical   movement  and  postural  disorders
    that follow asymmetrical lesioning of the special topological
    homeomorphism of the CNS. [Added 2003-12-21: These constitute
    surgically-induced localized functional "inversions".]

k. p. collins

More information about the Neur-sci mailing list