
Building a Brain on a Silicon Chip - 200K neurons linked up by 50 million connections - nickb
http://www.technologyreview.com/computing/22339/?a=f
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pygy
I'm a bit puzzled by these attempts at simulating the brain. I work in
neuroscience, but very far from this field so I'm most probably at the worse
point of the (estimated knowledge / actual knowledge) graph on this topic. The
people working on these projects are incredibly smart, and are certainly aware
of the following caveats, since they've been thinking about it for years. I'm
actually posting this comment hoping that someone will jump in to prove me
wrong.

This looks like a cargo cult to me.

Not "cargo-cult science" as denounced by Feynman where some nutjobs tried to
make telepathy or astrology look scientific. This is real, serious work, with
a sound methodological grounding.

I'm afraid that they are actually building a "cargo-cult" brain, because they
actually are at the wrong spot of the aforementioned graph too. Think of AI in
the 70's. AFAIK, we know far too little and the field is still too fragmented
to build a reasonable model of the meso- and macroscopic structure-function of
the brain (I'm actually unable to tell where one start and the other ends,
assuming the distinction between both concepts isn't a false dichotomy).

You cannot emulate a brain out of the box. You have to simluate the whole
embryologic developmental process (which is half directed (mostly at the
population scale), half random (at the microscale), but it's actually more
complicated) before you can start to educate it, assuming you built something
functional. Once again, we know, at the same time, a lot and close to nothing
about these development.

Brain simulation could be, oh the irony, a good target for genetic
programming/engineering :-).

~~~
sown
At the very least it would provide interesting FPGA technology.

I think most engineers recognize that the brain has a lot of unknowns.

When you say "educate" what exactly do you mean? We can train neural networks
now to, say, recognize handwriting or other behavior. I think we are just
after a system that can learn anything in general, say take a chess program
and then give it checkers. Or Magic: The Gathering.

Also, the field seriously needs people like you. It seems like there are at
lot of engineers who are into the brain and want to build stronger AI but not
many biologists who want to do the same.

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pmjordan
_The FACETS group now plans to further scale up their chips, connecting a
number of wafers to create a superchip with a total of a billion neurons and
10¹³ synapses._

I just thought that they were going to have some serious problems with yield
at that kind of scale, but then it struck me that that's kind of the beauty of
it: it doesn't really matter if a couple of neurons don't work - if it's
anything at all like a brain, it'll be remarkably failure-tolerant.

(based on my admittedly limited knowledge of brains, simulated brains and
semiconductor engineering)

~~~
jodrellblank
... And if it's anything at all like a brain, it'll be quite bizarre.

I really recommend this book - The Man Who Mistook His Wife For A Hat by
Oliver Sacks ( <http://www.amazon.com/Man-Who-Mistook-His-Wife/dp/0684853949>
) to change opinions of brains and people.

