Thursday, April 18, 2013

The neural substrate; astrocytes and information theory




How the brain was in 1911 - Encyclopaedia Britannica
  I left concept and demon as a Mobius strip.  That way is disaster.
  Salvation may lie, I suspect, sethren, in information theory and astrocytes.  About which I know, to be honest with you, fuck all.  Cells in the brain, glial cells.  It was thought that astrocytes merely provided scaffolding and maintenance.  I have no idea how numerous they are, but in the human brain there are about one hundred billion neurons, and astrocytes outnumber them considerably.  Two hundred billion? Ten thousand billion?  A lot.  Also, and this is the significant bit, they don’t just do structure, maintenance, repair, garbage removal and vermin zapping.  They do information traffic control the magnitude of which makes me dizzy.
  The sky tilts.  I  steady myself with a hand on the cold metal of the bus stop.  No, fine, thank you, fine.  I’m all right. But there's more.  While Professor Alcino Silva, from the Brain Research Institute at UCLA, says, "There is a carefully choreographed synaptic signalling dance between astrocytes and neurons...", according to  Maiken Nedergaard, "The volume of human astrocytes is almost 20 fold larger than their rodent counterparts, enabling human astrocytes to integrate input from a comparably staggering number of synapses, 2 million compared with 100,000 in the rodent brain."  Again, I touch the cold metal, not for support, but for the steadiness of the world.
  So in this dance of the astrocytes and the neurons, we are talking about numbers of possibilities so astoundingly out of, for sure, my intellectual grasp that we need not worry about the brain lacking the computational capacity to handle any hypothesis that my puny workspace may foist on it.  That’s my point, sethren.  And as a corollary, because the functioning of this astrocyte/neuron choreography is as yet imperfectly described, it would be vainglorious to try and ascribe locations and functions just yet.  For anybody.
  What I am saying, sethren, is that for the purposes of our endeavour here, it is quite respectable to treat the brain the other side of the language barrier as a black box; the location of an ideoverse; continuous with the metaverse and the universe; to build a hypothesis about this black box being (given its continuity with the universe and the metaverse) the place where culture evolves, including things like needles and the demon astrocyte; remind ourselves that, though our venture here is derisory compared with his, Darwin did in 1857 exactly what I am suggesting now, propound the theory before he understood its physical basis; and plunge onwards.  All we can lose is our dignity, the respect of the academy, and hours which otherwise might be spent wandering the streets hustling for any spare change.
  As for information theory, I know even less about it than about the working of the brain, and cannot consult my phone which has been found by the good workers of the Alhambra Theatre, Bradford, under a seat in row F, but which I cannot retrieve owing to lack of the wealth now demanded for a bus ticket.  “Fucking thumb a lift, yer daft git,” yes, sether Albert, a canny suggestion, as The Pitman Painters would say.
  The only thing I do know about information theory is that it is about economy.  Information is what causes a change of state in a system.  Anything else is noise.  I don’t want to knock language, human speech.  As I say, I use it all the time.  But a lot of human speech is noise, redundancy, ambiguity, sheer nonsense.  And, I make this assertion about the black box, the brain the other side of the language barrier; the neural substrate has little use for language.  Language is merely a cumbersome, somewhat shapeless and blurry form that demons in their numberless alliances assume when they journey out of one ideoverse and through the world to other ideoverses.  It is not a reliable system.  Because it is so overdetermined, it is one of the main places where mutation occurs.  Seldom does a demon arrive in exactly the form that it left.  As it transits through ear or eye and emerges on the ideoverse side of Wernicke’s area, it is likely to be co-opted by a similar demon jealous of its accommodation, and thus immediately mutated, the one becoming the other.  Such co-option across alliances of demons we call confirmation bias.  A signal that this mutation has been complete is when someone says, “Yes, I know exactly what you mean.”
  Information theory is the basis for economy, for the exclusion of noise and redundancy.  It informs, for instance, the cell phone system.  I guess the processes of the human neural substrate would not be found wanting by the prescriptions of information theory.  Thus it’s potential becomes orders of magnitude more vertiginous even than it was to start with.
  And that doesn’t matter a fuck to demons, sethren, to culture.  That’s where they thrive.  Culture does not evolve by making things clear and plain for its obligate symbiont, the human organism.  In fact culture is not at all keen on us knowing it’s there.  I sometimes wonder if it has its own phagocytes, its own glial cells, in their infinite trillions, to attack, consume and excrete, as noise at the limits of entropy, the kind of thing I am trying to say here.  But this is paranoia.  And as your hunger grows, sethren, and the wherewithal to pay Madam MeMe for her slurry is harder and harder to come by, all sucked away by the tapeworms of government and the financial industry, you will, by way of distraction, begin to cry out, “Stop your blather, man.  Have done with prevarication.  You were in a deep hole.  It suddenly came to you that every demon is a concept, and every concept a demon.  Get th’sel out of that fatal loop if th'can.”
  But first I had to set the stage, sethren; though to be honest for what enaction I know not yet.  Tomorrow I shall make the attempt, so we may spend the weekend at peace.

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