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From: yamauchi@CS.ROCHESTER.EDU (Brian Yamauchi)
Newsgroups: sci.nanotech
Subject: Re: How big is a brain?
Message-ID: <8903240501.AA22667@athos.rutgers.edu>
Date: 23 Mar 89 06:50:55 GMT
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>Problem 1: Design a chip to simulate a bunch of neurons.
>
>An estimate:  if we can simulate a neuron with a few thousand "circuits",
>we can probably simulate close to a hundred with the same circuits, since
>the transistors switch much faster than neurons react.  Assume that with
>100000 circuits (near the chip space of the 80286 processor,) we could
>simulate 1000 neurons in real time on one chip with current technology.
>Then we'd be talking on the order of 60 to 90 million chips (= 2^26) in a
>network, for each brain to be simulated.

It seems clear to me that if you want to attempt this brute force
method of brain simulation you want to use analog VLSI not digital.
Since you could acheive a component:neuron ratio that was much lower
(maybe almost 1:1).  If someone has accurate estimates of current
state-of-the-art analog VLSI capacity / performance, I would be very
interested.

Personally, I think we will have human-equivalent processing hardware
relatively soon -- but the software is the hard problem...

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Brian Yamauchi				University of Rochester
yamauchi@cs.rochester.edu		Computer Science Department
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