> Hi Philip
you wrote
> > I can see why this second type, positive feedback, could be used in modeling
> > tremors.
The removal of tremors is not difficult to model .What is difficult
to model is the improvement in PD symptoms by Pallidotomy . If one
models the brain as a series of electrical circuits and one maintains
that PD=lack of dopamine ( I dont like either but for the sake of
discussion ) . then lack of dopamine is equivalent to the electrical
connections in the circuit degenerating ( a higher resistance ) . I
find it hard to find a scenario where there could be an improvement
in function of this degenerated circuitry (PD )by removal of some components (
Pallidotomy ) . My own model can be found in the archives and I can
post it directly to anyone who is interested . I am always looking
for alternative explanations that may lead to a cure .
Electronically, this is Oscillator Theory and the next step is to
> > look at the "gain" of the system -- the state of the response to your meds
> > (amount of dopamine present?) NOW as a physicist/engineer I am over my head
> > in the biology/physiology/pharmacology of the brain and will stop here.
HI Joao
You wrote
> I am under impression that some explanation may derive from such a
> research .It would show any modification of the flux in the area of
> activities inside the brain (before compared with the after). Does
> someone in the list knows that this has already been done ?
Scans showing the pattern of blood flow in the brain before and after
Pallidotomy are different have have already been done . The
difference was considerable . IT affected the whole brain not just
the the pallidus .
peace
Alastair ( [log in to unmask] )
