Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!oliveb!apple!voder!berlioz!andrew
From: andrew@berlioz (Lord Snooty @ The Giant Poisoned Electric Head)
Newsgroups: comp.ai.neural-nets
Subject: Re: Biological Reality and Backpropagation
Summary: On the contrary...
Keywords: Backpropagation, Biology, NETtalk
Message-ID: <180@bach.nsc.com>
Date: 5 May 89 00:37:47 GMT
References: <2518@bucsb.UUCP>
Organization: National Semiconductor, Santa Clara
Lines: 18

In article <2518@bucsb.UUCP>, adverb@bucsb.UUCP (Josh Krieger) writes:
> Does anybody know of ANY biological evidence that supports the
> existence of backprop..

On the contrary, Stephen Grossberg ("Neural Networks and Natural
Intelligence") takes the opposed view - that weight transport, required
for BP, is a physically implausible mechanism. We had the BP vs. ART
discussion some months ago in this group; I received some interesting
responses.

The only "pro-bio-BP" argument I have heard addresses upper-level
symbolic processing levels, but it seems to me that Grossberg's
argument holds anywhere in the brain.
-- 
Andrew Palfreyman 		USENET: ...{this biomass}!nsc!logic!andrew
National Semiconductor M/S D3969, 2900 Semiconductor Dr., PO Box 58090,
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