Axon collaterals ?

Doktor DynaSoar targeting at OMCL.mil
Fri Dec 19 09:25:39 EST 2003


On Fri, 19 Dec 2003 04:13:27 GMT, "k p  Collins"
<kpaulc@[----------]earthlink.net> wrote:

} "Doktor DynaSoar" <targeting at OMCL.mil> wrote in message
} news:oue4uvsgfdqn37503bqc38f23ueh680b1p at 4ax.com...
} > On Thu, 18 Dec 2003 11:21:22 -0500, r norman <rsn_ at _comcast.net>
} > wrote:
} >
} > } On Thu, 18 Dec 2003 12:49:39 GMT, "Glen M. Sizemore"
} > } <gmsizemore2 at yahoo.com> wrote:
} > } [...]
} 
} > My money says the autapses are a tuning mechanism which makes the cell
} > tend to fire at a certain rate in the absence of other input. Think of
} > the "resting" oscillations of visual alpha, motor mu, auditory tau,
} > etc. I think this would probably be most evident in the GABAergic
} > interneurons that drive the 40 Hz "binding" (used here in the sense of
} > functional Hebbian assemblies, not that of experiential gestalt).
} > Something tunes them very tightly, and all the work trying to pin this
} > on some characteristic inherent in the cell membrane has been
} > unsatisfying.
} 
} Complete tuning cannot occur at the cellular 'level' because that'd
} render global integration [unified consciousness] 'impossible'.

As I said, I was speaking to activation of functional Hebbian
assemblies, not experiential gestalt, which refers to both the binding
of disparate perceptual and cognitive functions into a seeming unified
whole, as well as the fuzzy wuzzy playground where philosophically
inclined cognitive science wannabes collect and poke words at their
favorite self-imposed conundrum that they call consciousness.

I canceled my charter subscription to the Journal of Consciousness
Studies after vol. 3 #2, when they came out with an entire issue on
"zombies" and not a one of them could tell me where I could get one to
test in the laboratory. 

You see, I stick wires in things. I'm a laboratory scientist. To date,
no one has pointed at anything I could stick a wire into in order to
measure the presence or lack of "consciousness". And to date, every
"definition" of counsciousness (I put definition in quotes because a
defnition should be a reduction in abstraction, and all exhortations
of consciousness have been quite the opposite) has failed to encompass
non-conscious actions of a conscious mind (para-attentional processes)
and the effects on the conscious mind of information acquired
non-consciously (learning under anesthesia).

I *can*, however, demonstrate intrinsic oscillatory activity in
neurons, demonstrate that various cytoarchitectural populations have
different intrinsic oscillation rates, and that they can vary their
rates under different processing loads. Furthermore, I can make a darn
good argument why the hypotheses regarding both membrane
characteristics and neural network models are insufficient to explain
the robustness of the state attractor for the various oscillatory
processes.

} In other words, if it were so, then every neuron would have to
} possess the ful functionality of the entire nervous system, which,
} then, instantiates the larger 'problem' of explaining why more than
} a single neuron is necessary.

Since it is so that such tuning occurs (keep in mind, I was suggesting
autapses as a mechanism for it; the existence of the phenomenon is not
in question), then obviously your assertion is incorrect. However, it
becomes clearer and clearer you had no intention of even addressing
it, but rather were merely looking for an opening for an entirely
dissociated rant. To wit:

} [But, please Forgive me for pinning this essay to your post. It just
} needed to be worked-in somewhere, and your post constituted
} an opportunity to do that. I'm actually addressing my comments
} to folks who've had access to a much larger discussion that's
} occurred here in b.n over the course of the last decade+.]

You addressed your comments initially to mine, and you were wrong.

Here's something to wash down the above with: 40 Hz gamma
synchronization occurs preceedingly processing by populations of
cortical neurons. This is the electrophysiological signal so beloved
by the JCS folks as candidate for "consciousness". Yet it seems to be
one of the most evolutionarily ancient of neural processing signals.
It occurs in nearly every multicellular processing assembly above the
direct-connect ganglion level. It occurs in flies' eyes. It occurs in
locusts' probiscus. And to quote my mentor, Karl Pribram, "It's going
on in your butt right this second. You don't think your butt is
conscious, do you?"




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