🚀 go-pugleaf

In article <876306121snz@longley.demon.co.uk>,
David@longley.demon.co.uk (David Longley) wrote:

>Another  point on the whole issue of "temporal neurone"  is  that 
>what's been presented so far is just pretty standard contemporary 
>classical conditioning. It's been known for 30 years that  strict 
>contiguity is not enough for association and I've outlined one of 
>the most influential models here several times now.

  It may have been known for some time from work in classical
conditioning that temporal order was important (and I agree) but it
was not until very recently (Henry Markram, January 10, 1997 issue of
Science) that part of the actual neurophysiological mechanism
(antidromic spiking) was discovered.  This is a major breakthrough,
IMO.

> The Rescorla-
>Wagner model of 1971 provided the first good summary of the  data 
>covering "blocking", and Rescorla's earlier work in 1968  showing 
>that  the CS needs to bear an "informational", more accurately  a 
>contingent, temporal relationship to the UCS. Simultaneous events 
>on   the  other  hand  result  in  overshadowing,  and   backward 
>conditioning  very  little if anything.

  I've acknowledged the importance of work in operant conditioning.
This work however sheds no light on the actual mechanism at the single
neuron level.  Without a knowledge of this mechanism, no progress can
be made.

> But a  temporal  relation 
>alone  is not sufficient (as Kamin showed long ago). If one  goes 
>beyond  "delay",  to "trace" conditioning, it looks  like  higher 
>levels of processing such as the hippocampus is required - but as 
>I've said before, this is already getting into levels of learning 
>in the neuroaxis...

  I'm sorry, this is nonsense.  A signal is but message indicating
that something happened at a specific time.  The neuron processing the
signal has no idea what that something is and could not care less.  It
only gets the signal and that is it.  To make sense of anything it
needs to find several signals to determine their relationships, if
any.  Temporal relationship is the **only** type of relationship that
can exist between events (signals).  Period.  David, you are falling
headlong into intensional superstition here and your appeal to
obsolete authority makes it worst.

>What  I see here in these threads is some excitement on the  part 
>of  proponents  of  this work, but it seems  to  reflect  "their" 
>personal  discovery  of something which a large number  of  other 
>researchers have been working on in the context of small  systems 
>models  (Richard Thompson's group) for several decades now.  That 
>work  makes no claims to being able to build "learning  machines" 
>on the other hand, just unravel some of the neuromechanics behind 
>basic conditioning processes.

  The actual physiological mechanism responsible for temporal
processing is only now making it to the surface (see the above
reference).  All we had before that was behavioral studies in
classical conditioning.  Not much more.  I do agree however that
classical conditioning tells a powerful tale about biological learning
but we are pragmatic technologists and we need hard *mechanisms* to
work with not just observations of behavior.

>To be a breakthrough, a discovery has to be more than one getting 
>excited   about   something  one  learns  -  to  be   a   genuine 
>breakthrough, one needs to know the literature and be working  in 
>the field to know what is and is not new and worthy of attention. 
>How else can one ascertain whether it is indeed a breakthrough?

  Sorry, you have no idea what you are talking about in the context of
recent work done in neuroscience.

>If you want to make any real progress on "learning machines"  you 
>are  going  to  have  to come to grips with  the  issues  I  have 
>discussed elsewhere, 

  David, your fascination is with deduction and that has absolutely
nothing to do with learning.  So you could not possibly understand
anything worthwhile about the subject.  Learning is forcibly inductive
and this is the pure extensional truth whether you like it or not.

>the most important of which is that most  of 
>our psychological idioms, including those of learning and memory, 
>are  intensional idioms, not the stuff a science  and  technology 
>can or should be grounded upon (and to fully appreciate that, you 
>need to know the literature).

  More nonsense.  Work in computational science is not based on
intensional idioms but on hard scientific data.  Por favor David, do a
little research in this area before offering your opinion or
criticism.  In conclusion I'll just repeat a powerful extensional
truth that seems to escape you and others:

               Temporal relationship
               is the only type of
               relationship that can
               exist between events.

  Therefore, intelligence and learning must be about temporal
relationships.  Nothing else.  Deny at your own risk.

Regards,

Louis Savain

President, Marengo Media, Inc.

Here are some relevant sites:

http://www.hhmi.org/communic/bulletin/oct95/crack.htm
http://www.sciam.com/explorations/020397brain/020397explorations.html
http://www.cs.stir.ac.uk/~lss/AntiDromic/AntiDromic.html
http://sanjuan.cs.wwu.edu/mobus/
http://www.sat.t.u-tokyo.ac.jp/javier/wsc1.html
http://www.klab.caltech.edu/
http://www.cnl.salk.edu/CNL/