Basic Neuron Questions
k.p.collins at worldnet.att.net%remove%
Mon Apr 7 10:35:25 EST 2003
"BilZ0r" <BilZ0r at TAKETHISOUThotmail.com> wrote in message
news:Xns9356B3A601FF7BilZ0rhotmailcom at 126.96.36.199...
| >| Yes there is, Its defined by the time it
| >| takes for the potassium channels
| >| to be available for opening again.
| > That this or that is "defined" to be that
| > or this does not make this
| > or that that or this.
=Every= ionic conductance, including charged macromolecules, enters
into that which you refer to "potassium channels" - or do you suppose
that, somehow, "charge" is not =always= "charge"? Do you think K+
sees only K+? That Na++ sees only Na++? Do you think K conductance
can exist without Na conductance?
All ionic "channels" respond to the net ionic "charge" - of course
with respect to their specifically-'engineered' "gate" correlates,
but there's a whole 'world' in-there that enters into the
determination of the specifics.
For instance, neural glia act as K+ "electrodes", redistributing K+
concentration gradients in accord with ongoing neural activity.
Saying this or that is that or this doesn't make tthis or that that
One has to get in-there and follow the ionic conductances before one
can discern =anything= with respect to a k+, or other ionic "gate" -
in vivo, 'resting' potentials, etc., vary[everything "ionic" varies]
in accord with the ionic background.
If one wants to have coctails at conferences, one needn't follow the
ionic conductances, but if one wants to comprehend CNS function, one
must do so.
No "ideal cases" - no "absolutes" - everything's relative to the
ongiong ionic conductances.
| Actaully its sodium channels, I've been
| feeling like an idiot all day,
| was at work and couldn't correct myself.
Obviously, you're not an "idiot". You;ve just read the books and left
out the most important thing - to think.
NA++ same-old, same-old.
Anything ionic, same-old, same-old.
Of course, with respect to specifically-'engineered' "gates", etc.
The quantity of work a gate must perform against the ionic background
encodes the 'state' from which learning-correlated microscopic
trophic modifications gain their information-contents.
Everything within nervous systems is rigorously-coupled to WDB2T.
The work-encoding with respect to WDB2T is how information is stored,
cross-correlated, and retrieved within nervous systems.
| Theres a "conseptualization" thats wrong. If I define something as
| something, that is the only thing I can be sure that it is.
| X=2, now I know that X=2.
But if your definition stands before you as a 'closed door' that
prevents your seeing what's necessary to see, your "deinintion" is
nothing more than a 'brick wall' that's worthy of nothing other than
being 'torn down'.
What good is a "definition" that 'blinds' you?
| > The =only= "absolute" that exists within
| > Living nervous systems is that their functioning
| > rigorously conforms to WDB2T.
| the absolute refractory period isn't called
| absolute becasue we know exactly what
| it is. Its called that to outline the different
| between it and the relative refractory period.
In vivo, no such thing as an "absolute refractory period" has any
existence. It's all as above, with respect to the ongoing ionic
| > The rest is dynamic as a function of experience.
| > No neuron is ever in the same 'state' twice
| > because all neurons undergo microscopic
| > trophic modifications as a result of the activation
| > that actually occurs within them, and the rest of
| > the neural structure in which they are embedded
| > - all the way up to the nervous system as a whole.
| > Such feeds-back into the ionic concentration gradients which
| > determine the stuff that you were non-existent-ideal-case
| > short-shrifting, with the result that the 'ideal case' is total
| > fiction.
| >| > [...]
| >| > Within Living nervous systems, there exists
| >| > no such thing as "normal" levels of stimulation.
| >| What? Yes there are. look at any monosynaptic
| >| nevous pathway.
| > As above, there exists no such thing as a neuron
| > whose energydynamics occur as the sole result
| > of synaptic 'events' - the synaptic 'events',
| > themselves, occur as a function of whole-nervous-
| > system energydynamics.
| > If it were as you say, to the degree it were so,
| > the 'nervous system' in question would be a
| > non-learning automaton.
| The normal level of stimulation. The level at which
| is would normal fire an AP at. The threshold of
| activation. Call it whatever you want, if you
| want to argue that there is no such thing, you're
| going against what everybody bar you thinks.
"What everybody thinks" is wrong, as above, because "everybody"
doesn't get-in-there with the ionic conductances - as above.
There's =nothing= 'static' within nervous systems. Everything is
'tuned' with respect to the ongoing conductances. This's where
"intelligence" arises - in the quantities of work that stuff like
"gates" ["punps", etc.] perform, the rigorous correlation to WDB2T
becomes established - this's how nervous systems "know" what ever it
is that they [via TD E/I-minimization] converge upon "knowing". All
information is work-encoded within nervous systems in this way.
Everything within nervous systems is 'linked' together in terms of
The neural Topology establishes the substrate in which the
work-distribution is "recognized" - from the ionic 'level' all the
way up to effector-driving, with cognition in-between - =everything=
The easiest way to get an initial 'handle' on this is to study the
motions of your hands as you are performing externally-relevant work.
Calculate that work, then follow it back into your nervous system.
Throughout, it's all the same stuff - calculating with respect to
The calculations can be performed by nervous systems because WDB2T
permeates physical reality in a way that is consistent.
That is, there are local variations in WDB2T, but no matter the
vairiance [within the bounds of what's survivable], nervous systems
are able to 'sense' its 'meaning' in terms of the work that dealing
with it entails.
Is it freezing-cold outside? -> do the work necessary to find a
more-favorable WDB2T energy-gradient [to find 'warmth'].
Is it hot? -> do the opposite.
It's all 'moving toward', or 'moving away from', with respect to
| >| What I can't say how fast a action potentialtravels?
| >| Lol. Not exactly, but I can give the accepted range.
| > It's like I said, OK at an introductory 'level', but totally
| > if one actually wants to comprehend how nervous systems work.
| > Clearly, if it's "bionet.neuroscience", we're beyond the former,
| > interested in the latter.
| I don't think the poster was interesting in
| comprehending the nervous system as a
| whole. He wanted to know how far a AP
| travel during the absolute refractory period,
| so I told him.
I explained why I 'jumped' your post.
The books are 'stepping-stones' upon which one can 'stand', but only
to see-further, not 'dictators'. And if they're left as the latter,
then either the Author of the Reader has failed.
The questioner was best-served by telling him where to go to start
thinking, not what to think.
That, and that you've been 'jumping' my posts as if you think I'm
some sort of 'crack-pot', and that always gets my 'attention', sooner
I mean no 'offense', but there's Truth on the line, and I 'move
K. P. Collins
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