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From: ins_atge@jhunix.HCF.JHU.EDU (Thomas G Edwards)
Newsgroups: comp.ai,sci.bio,sci.psychology,alt.cyberpunk
Subject: Re: The Bandwidth of the Brain
Summary: Attentional information filtering
Message-ID: <7210@jhunix.HCF.JHU.EDU>
Date: 18 Dec 90 08:17:54 GMT
References: <37034@cup.portal.com>
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Organization: The Johns Hopkins University - HCF
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In article <37034@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes:
>There is a common myth that the brain is capable of enormous computational
>bandwidth -- for example that the retina sends gigabauds worth of data to
>the brain.  I believe the computational bandwidth of the brain is quite low,
>low enough that we could simulate a brain on today's computers if only we knew
>how to do it.

As far as visual processing goes, we know that a huge amount of the
information which arrives in the retina is filtered out before we
do serious cognitive processing.  But there still is a huge bandwidth of
visual information which is available to pre-attentive areas in brain,
thought most of the pre-attentive visual processing is highly parallel.

Also I think we are finding that what looked like near random nerve 
pulses are actually frequency and phase modulated (i.e. more bits per
baud, just like a 9600 BPS modem). 

I will most strongly agree that post-attentional areas in many types
of perception probably deal with alot less information than one would
naively think, but the real challenge to artificial neural systems
is performing the massive attentional task at hand.

-Tom