neurotransmitter storage (all or one?)

dag.stenberg at helsinki.nospam.fi dag.stenberg at helsinki.nospam.fi
Thu Aug 31 03:15:45 EST 2000


Theophilus Samuels <theophilus.samuels at btinternet.com> wrote:
> My thinking is as follows. I tried to introduce a concept earlier on, but
> no-one seemed to notice. The concept was Frequency coding. As stated, the AP
> is an all or nothing event, to requote 'it doesn't mess around'. Now here
> lies the difference between the randomness of an analogue system based on
> graded responses (this was the original argument) and that of this one -
> TIME. If we have 5 AP being fired by a single neuron, the time intervals
> between each of them could be more easily collected and processed. But now I
> hear you say, we have no element in our brain that counts time on such small
> scales! And quite right so. Here lies a big leap of faith, the brain somehow
> knows how to interpret these signals. ...

Yes, but...
Even if we agree that the input to a neuron consists of numerous events,
all of which are binary if we reduce them to their basic elements 
(channel open - closed, protein phosphorylated or not, gene transcripts 
or not, etc. ), and that they end up in frequency modulating the APs, 
we get little further in evaluating the effect of that neuron, 
because at its output end, there is again D/A modulation: each 
single AP can produce varying amounts of transmitter due to the 
circumstances, and the train of APs at changing (and 
information-containing) frequency is not the only factor that
influences the analog output of this neuron.

Dag Stenberg






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