Ion channel "quantization"
john at nine7.demon.co.uk
Wed Aug 14 03:17:52 EST 1996
In article <4uoljg$1l2 at newsbf02.news.aol.com>
radams2000 at aol.com "RAdams2000" writes:
> Here is a basic question from a "novice" in the field.
> I have read that at the dendrites of a neuron, the current flow into the
> neuron across the synaptic junction consists of some large number
> on ionic channels that are either completely open or completely closed.
> So it would seem that, according to how many channels are involved,
> the current flow into the soma is highly "quantized", meaning that only a
> finite number of possible currents can exist. Does this contribute to
> a fundemental noise mechanism in the process of neural firing? Can this
> noise mechanism be measured accurately? Is it modelled in any of the
> popular neural simulation packages??
> Thanks for any replies!
> Bob Adams
In electronics (my trade) when a comunications line is used to the edge of its
bandwidth of information transport, it canot be all on or all off.
This is more understood if one looks into modulation techniqes.
Fourier maths analasis of the waveform can breakdown the signal into
fundamental simple signals, showing that even an on - off digital waveform is
actualy not truly on and off.
Compression techniqes are simarlar in that they convert for transport but more
efficently, by useing up transmission time without so many repetions of whole
word spelling for example.
Nature is well known for efficent use of energy and resources, so why not the
comms, in the brain.
In electronic communication there are set definitions internationaly that have
evoved out of all the permutations, into a hierarchael system with context at
the top and hardware at the bottom.
Indeed studying the history of comms may show how each simple part has been
added to make the complex whole.
Maybe comms evolution is the macro equivalant of what has happened in the
brains evolution directed by simarlar natural constraints.
Just out of interest.
I have studied electronic neural networks and brain neural networks in my own
I find the waveforms in brain networks remind me of multiple modulation.
A good example of this in electronics, is mains powerd baby alarms.
The microphone near the baby creates a wave, which is superimposed on to the
mains supply wave.
In the brain wave diferant frequancys may be carrying info, seperate from other
frequancys in the range.
The amplitude can be varied or the frequancy can be and even the phase.
The way a recieving group network recognises the part of the signal for itself
could be by just learning to recognise the bit meant for itself like listening
to someone in a crowded room.
May be its leaned to look for a sequance of somthing before it listens or more
general characteristic than that even.
Recognition via some hardware direct contact
mechnism chemical or electical in any of 4 dimensions ie recent time or place.
Hope I not ranting like an amateture--Yours sincerely....John G.*?*?*?*?*?*?*
Us Neuron's don't KNOW that much, period.
*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*?*? (Everybody wants to be certifiably
nice on this tide of awesome tech' power.)c? (Posts mispelt or not should be
written with content to be worth saving so as apathy doesn't drown lurkers)c?
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