
Building a fly brain in a computer - breck
https://www.cifar.ca/cifarnews/2018/10/25/building-a-fly-brain-in-a-computer
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anonlastname
All they did is train a neural network to recognize flies. they haven't
replicated the nervous system of a fly. To say they "built a fly brain" is
wrong because that actually has been done for nematodes and it's different.

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jobigoud
Can it feel pain? I know pain is kind of tricky to evaluate in biological
insects as well but that's a discussion we will have to have at some point.

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viraptor
I don't think simulated brains can feel pain any more than a float variable
"current_pain_level" set to 100 can "feel pain".

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andyjohnson0
> I don't think simulated brains can feel pain

I'm not sure why you say that. Does pain have some property that makes it
impossible to simulate?

If an organic animal can feel pain and it is possible to create a 100%
accurate computational simulation of that animal, then the simulated animal
must also experience pain. To me the interesting questions are at what level
of simulation fidelity <100% (a) does the simulated pain be said to be "real",
and (b) does it make sense for the simulation to be said to give rise to a
subjective experience (if at all)? And the follow-on questions for both are
"how?" and the "why?".

This whole issue of simulated pain is part of the premise for Roko's Basilisk
[0].

[0]
[https://rationalwiki.org/wiki/Roko%27s_basilisk](https://rationalwiki.org/wiki/Roko%27s_basilisk)

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gambiting
To quote a book I hold in very high regard:

“Opponents replied that when you modeled a hurricane, nobody got wet. When you
modeled a fusion power plant, no energy was produced. When you modeled
digestion and metabolism, no nutrients were consumed – no real digestion took
place. So, when you modeled the human brain, why should you expect real
thought to occur?” ― Greg Egan, Permutation City

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andyjohnson0
I also hold that book and it's author in high esteem, but I don't find that
quote very useful. Nobody gets wet when you model a hurricane because the
model's purpose isn't to make people wet, it's to predict the dynamics of the
hurricane at some level of detail. Same goes for fusion plants and biochemical
processes.

The _purpose_ of a hurricane isn't to make people wet, it's a by-product. If
you wanted a simulation that made people wet then that could be arranged,
either by modelling rainfall on simulated people or having a simulation that
controlled physical water sprays/sprinklers suspended above physical people. I
don't know what that would prove though.

And going back to _Permutation City_ , (spolier) the whole premise of the book
was that brain simulations _did_ have real subjective experiences that were
qualitatively indistinguishable from those that occur in "real" physical
brains.

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bastih
It's interesting to see biological system and implementation next to each
other. Are there any similar visualizations for other ML-implementations?

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speps
This is a similar project: [http://openworm.org/](http://openworm.org/)

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Phemist
Very cool! Takes me back to the days when I first studied Laughlin's short
paper on fly eyes [1]. Amazing how we've gone from this early experimental
result to something as complex as simulating a full visual system!

[1]
[https://www.ncbi.nlm.nih.gov/pubmed/7303823](https://www.ncbi.nlm.nih.gov/pubmed/7303823)

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psk0
I couldn't see whether they have ruled out that ML is clustering based on the
image noise and lighting.

I wouldn't be surprised if the same clustering is achieved after masking
big/essential chunks of the fly from all the images (for training and testing
sets). If indeed the 'imaging features' are the driving weights in clustering,
that means the flies should be able to recognize that they are in a different
room.

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greenstonekid
I wonder what the computational difference between the fruit flies visual
system and the computer system used to run the model is?

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bwbw223
Sounds buggy...

