Wavelet answer: Re: question: job of a neuron

John H John at faraway.com.au
Fri Sep 7 23:47:18 EST 2001

Thanks Richard,

I'm not in a position to judge the wavelet idea, and one of my internal
rules is to try (!) to avoid making judgements about things I don't
understand. Hence my final question about testing it against a simple
nervous system. That seems to me to be the next logical step in the exercise
and for the purposes of proving\disproving wavelets the best possible

John H.

Richard Norman <rsnorman at mediaone.net> wrote in message
news:5sfhptkrmvm05edg0k8i57a07rcj5ojg33 at 4ax.com...
> On Fri, 7 Sep 2001 21:52:01 +1000, "John H" <John at faraway.com.au>
> wrote:
> >
> >"Ron Blue" <rcb5 at msn.com> wrote in message
> >news:009301c1362a$6144a6e0$ce02030a at RBlue...
> >>
> >> Unfortunately, the rules we learned in school don't seem to apply to
> >> real world.  Standard models are not standard, consider the summation
> >> in dendritic fields that would be dendrites talking to dendrites.
> >Normally
> >> information is thought to flow from dendrites to soma to axon to
> >> but this
> >> is not always true.  Neurons did not read the same rules that we
> >> did.  Consider the resent observation that glial cells transmit
> >information
> >> when we
> >> were told that their job was to support neurons.
> >
> >
> >It is nice and easy to say that neurons transmit, glia and astrocytes
> >support, but the division exists in our heads abstractly, not concretely.
> >Glia are important regulators of neural transmission and astrocytes
> >play some role also. For that matter, we need to remember that cytokines,
> >typically associated with immunological activity, also have a direct and
> >significant bearing on neural transmission. How does this all fare for
> >connectionist models of neural transmission, which imply direct
> >as the only means of neural transmission?
> >
> >For eg. Nitric Oxide. Nitric oxide acts as a neuro and immune modulator
> >through direct contact but through diffusion to various regions in the
> >immediate cellular region. It has a half life of circa 30 secs and
> >rapidly, affecting not only the generating cell but often its immediate
> >neighbours. This effect on transmission will be contingent upon the
> >of the 'target' to the site of nitric oxide generation,
> >the rate of NO diffusion through the cell cytoplasm, and the general
> >metabolic activity of the relevant cells at the time. 'Excess' NO can
> >all hell break loose then watch neural transmission struggle(the immune
> >mediated part). That's the trick though, the neural transmission can
> >intact for a very long time, all the while with neurons dying all over
> >cortex and underlying metabolic processes  challenged.
> >
> >The primary goal of brains is not to 'process information' but to
> >an appropriate response to environmental(internal and external)
> >contexts.Given the variety of metabolic contexts in which brains must
> >achieve this primary goal, I struggle with the idea that just observing
> >neuronal activity will give us ALL the insights into how neurons do their
> >work. The neuroscientists are well aware of this but too often I get the
> >impression that the AI people overlook this, preferring simply to think
> >about neural transmission as some
> >singular isolated process quite independent of the rest of the body. So I
> >wonder if Inhibitory neurotransmitters\modulators, which I believe
> >in frequency as brains became more complex, play a key role in helping to
> >control noise.
> >
> >It is useful to remember that nervous systems evolved collectively,
> >and glia and astrocytes all having their part to play, not to mention the
> >rest of the body. Nervous systems must not only contend with their own
> >internally generated activity(including sensations) but also contend
> >with\incorporate other signal types from the body that can signficantly
> >modulate neural activity. Whatever neural transmission is, it must be
> >to cope with a plethora of signal types and volumes.
> >
> >What I like about your approach Ron is that it provides avenues to
> >overcoming the continual noise and fluctuating contexts under which
> >must function. "Fuzzy processing" is the norm of brain function, not the
> >exception. What I would like to know is: can you test your model against
> >simple nervous system?
> >
> >John.
> >
> I agree with most everything you say -- and it is very well put --
> almost. Beyond your "liking Ron Blues approach (" do you really
> believe in wavelets?) a technical quibble.  You speculate whether
> inhibitory/modulatory processes increase in  frequency as "brains
> become more complex".  Actually, inhibitory and modulatory processes
> have been around for a very long time.  Consider the crustacean
> stomatogastric ganglion, about the smallest known neural system (some
> two dozen neurons).  It works entirely on inhibitory and modulatory
> interactions between the cells.   You can't get "simpler" than that,
> yet it is incredibly complex in cellular activity.

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