Synaptic modification rules ?

Peter F. effectivespamblock at ozemail.com.au
Mon May 24 03:37:34 EST 2004


"Matthew Kirkcaldie" <m.kirkcaldie at removethis.unsw.edu.au> wrote in message
news:m.kirkcaldie-C3D8E4.15465020052004 at tomahawk.comms.unsw.edu.au...

> There are interesting ideas about other possibilities though - for
> instance LTD in the ventral tegmental area, which may be responsible for
> addiction, operates via a non-NMDA-mediated plasticity.  It may boil
> down to the presence or absence of a co-factor - such as stimulation of
> serotonergic synapses at the same time as glutamatergic (one of the
> protocols used in the synaptic capture stuff coming out of the Kandel
> lab) or the trafficking of appropriate biochemical machinery to
> appropriate places in the cell at certain times.
>
> Of course these are only distractions in the face of the real question,
> "why do the properties and functions of neurons differ?", which, in its
> most basic form, is "why is the nervous system the way it is?"  Not too
> many (worthwhile) books on that subject!
>
"Being too haughty or too humble can, both, cause one to stumble."
(Proverb from the annals of EPT ;-))

So (just to make it seem that I know precisely how what follows follows), it
remains to "take the bull by the horn" and accept that, given the complexity
of "What Is going on", we cannot ever achieve completeness in our quest for
comprehension; but that we nevertheless can grasp 'more' of Infinity
(including what goes on inside ourselves) than feels comfortable.

E.g., it can be useful to understand neurons against the background of the
"Evolutionary Pressure Totality" -- which can be taken to include, amongst
else, "opportunity and adversity type" environmental challenges (or
pressures) of individuals of phylogenetic populations relevant to the human
(or some other neural animal's) lineage -- and thus, that the ways neurons
'behave', and the roles they play, to an important extent reflect a
"sum-over-histories" [here mainly loosely pertaining to a 'signal detecting,
noise stacking/canceling, both somewhat statistical and Category Theory-like
method of thinking] of naturally selected individual mutants who manifested
neurologically significant genetic variation in context of correspondingly
significant types of lifetime (individually lived) situations.

I am sure it can be put in simpler terms - but then it would not be as
in-dEPTh. :-)

---
People like you and Neil have, as far as I can see, already enough
scientific ammunition (factual information and strong or best bet
indications) to shoot for bigger and uglier beasts than it seems to me that
you currently humbly aim for.

For one, I bet you could easily back-up my conclusion (if you only cared to
concur ;-)) that a phylogeny filled with certain types of irregularly
occurring inescapably adverse situations can implore, and would have induced
in one or more mutant ancestor of ours, a specific or local  "synaptic
Hibernation" (LTD of synapses within a dendritic tree) -- akin to how, with
seasonal regularity occurring harsh winters or draughts have resulted in
animals that hibernate or aestivate to a global (organismically so) extent .

The common denominator (unifying psychophysiological feature) of all these
adaptations to ~HITSS~ (Hibernation Imploring Type Seasonal Stressors and
Sporadic such Stressors) being: a selective canceling of behaviour and
Consciousness (or a 'preconscious preclusion' of SHITS-specific focuses of
actention), and a crucial dampening of a correspondingly particular
functural (functional + structural) pattern of metabolic activity.


Anyway, whether you understand me or not, I like reading much of the posts
by people like NMF and yourself.
:-)

P







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