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From: stevens@prodigal.psych.rochester.edu (Greg Stevens)
Subject: Re: Men : Analogical or Digital ?
Message-ID: <1995Jun13.200107.17303@galileo.cc.rochester.edu>
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Date: Tue, 13 Jun 95 20:01:07 GMT
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In <3rjvt4$cub@gnu.mat.uc.pt> Pedro Miguel da Fonseca Marques Ferreira <pmferr@pardal.dei.uc.pt> writes:

>It has been some time now that a coleegue of mine and myself found
>ourselfs discussing about the following question:

>	Is man brain analogical or digital ?
>	(or is it none...)

This kind of argument can ultimately lead to a "is the natural universe
analog or digital?"  Otherwise stated, "Is the natural universe continuous
or discrete?"  There is no way of telling this.  The notion that "neurons
either fire or they don't" seems to imply that our perception is inherently
digital, except that this is a simplistic view of how neurons work -- they
can fire at a wide variety (continuous even?) of different rates.  So
maybe our perception is continuous.  Maybe the universe is continuous and
the connectivity of our neurons (center-surround cells, etc) is an
attempt to account for that continuity even though each neuron has
discrete activation. Maybe the universe is dicrete and we simply think
it is cxontinuous because of this connectivity.  Why knows?


>	The colors our brain can distinguish are 16.7 million.
>	Those are color levels.
>	So i think the human brain does a analogical to digital 
>	conversion of the analogical ( maybe ) stream of info
>	coming from our eyes.
>	What do you think of that ?

I think that colors are perceptual phenomena and tell us nothing about
"conversions" the brain might be doing, analog or digital or
otherwise.  Colors do not correspond to "wavelength" or "surface
reflectance" or any of these things -- merely with how our neurons
fire. 

Greg

