
No Brainer (2015) - Tomte
http://www.rifters.com/crawl/?p=6116
======
gwern
the scans are actually of a retarded person with hydrocephalus, and are not
scans of the near-mythical never-verified anecdote from Lorber
([https://www.gwern.net/docs/iq/1980-lewin.pdf](https://www.gwern.net/docs/iq/1980-lewin.pdf))
of the 126 IQ guy (Hawks gives a couple reasons why that might not have been
as impressive as it seems:
[http://johnhawks.net/weblog/reviews/brain/development/ten_pe...](http://johnhawks.net/weblog/reviews/brain/development/ten_percent_brain_myth_2007.html)
).

So the best example doesn't have hard fMRI scan evidence, and the documented
cases of hydrocephalus going along with an IQ of 70 or whatever are much less
impressive - if you think the brain is doing something, you would expect
profound deficits like that!

More interesting is a recent paper: "Miniature spiders (with miniature brains)
forget sooner", Kilmer & Rodriguez 2019
[https://www.gwern.net/docs/psychology/2019-kilmer.pdf](https://www.gwern.net/docs/psychology/2019-kilmer.pdf)

~~~
GlenTheMachine
I don't know, the mere fact that someone with brain damage that severe could
even be conscious and interact with the world is pretty damned impressive to
me. An AI with that kind of systemic damage would present a Blue Screen. The
difference between vegetative and able to take an IQ test is far, far higher
than the difference between an IQ of 70 and one of 130.

~~~
nabla9
Dropout is regularization technique in deep learning that works little like
like that. Randomly selected neurons are ignored during training, typically
the probability is 0.5. This means that half of the neurons don't work.

In other words, the network is trained with 50% 'brain damage' to make it
learn better and become more robust.

~~~
Life_exe
Dropout is not deletion. The neurons turned off will be lit in the next run,
and all would make into the model (brain).

------
jsharf
Does this remind anyone else of the lottery ticket hypothesis deep learning
paper that was published recently? [0]

I think the gist was that neural networks are usually much larger and more
connected than necessary. The paper provided an algorithm to iteratively prune
connections by seeing which links in the neural network had the lowest
weights.

Here's a quote from the paper:

"The Lottery Ticket Hypothesis: A randomly-initialized, dense neural network
contains a subnetwork that is initialized such that—when trained in
isolation—it can match the test accuracy of the original network after
training for at most the same number of iterations."

[0] [https://arxiv.org/abs/1803.03635](https://arxiv.org/abs/1803.03635)

~~~
sbierwagen
Or EfficientNet, SOTA performance with a tenth of the compute:
[http://ai.googleblog.com/2019/05/efficientnet-improving-
accu...](http://ai.googleblog.com/2019/05/efficientnet-improving-accuracy-
and.html)

You would hope the human brain would be pretty efficient, given the selection
pressure but apparently not.

~~~
jsharf
I mean, it's pretty incredible and coincidental that we evolved brains this
sophisticated in the first place, out of a totally random process with
selective pressure. After 13 billion years, I mean I think it's reasonable
progress, but I wouldn't expect SOTA efficiency. Once you have intelligence,
the evolutionary benefits are huge. There's all of a sudden not as much
pressure to be efficient (well there was, for like 100,000 years, but then we
invented fire and could cook, and that made getting energy/nutrition more
efficient. FYI, at this point I'm just quoting from the book Sapiens)

------
agbell
I love Peter Watt's writing. If you haven't read Blindsight I totally
recommend it.
[https://news.ycombinator.com/item?id=18378221](https://news.ycombinator.com/item?id=18378221)

~~~
AnthonBerg
Seconded. I honestly don’t see the world exactly the same after I read it.

------
tomxor
> Right now, right here in the real world, the cognitive function of brain
> tissue can be boosted— without engineering, without augmentation— by literal
> orders of magnitude. All it takes, apparently, is the right kind of stress.

The implied benefits assume the effect would be cumulative... but perhaps
sheer brain mass is not the limiting factor in a body, which is why these
cases aren't as detrimental as expected. i.e smaller mass of brain tissue
tries the best it can to fill the potential available to it.

As a crude and purely fictitious example: what if something in the brain stem
defines how much useful contentedness can be exploited? similar to how a north
bridge defines to some degree how useful a "capacity" of CPU is - More is
still better, but for many tasks there are diminishing returns past a certain
point due to the basic bandwidth limitations.

In this analogy these people would still have a fast bus, but a rather small
CPU - but you can still do a lot with that CPU and fast bus if you use them in
the right way and were forced to.

------
dang
Discussed at the time:
[https://news.ycombinator.com/item?id=10810454](https://news.ycombinator.com/item?id=10810454)

