
In the Human Brain, Size Really Isn’t Everything - wrongc0ntinent
http://www.nytimes.com/2013/12/26/science/in-the-human-brain-size-really-isnt-everything.html
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joe_the_user
One interesting aspect is that it assumes the animal brain is great for some
things but less good for logic-based flexibility. One might argue that human
intelligence is animal intelligence "virtualized" by language and
consciousness.

The idea is appealing but I have no idea if its true.

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Sniffnoy
The title seems a bit odd, seeing as the hypothesis described seems to be
describing a way that expanding brains _can_ (or did) lead to higher
intelligence. No, it isn't "just scale everything up", but it still has size
as a major controlling factor.

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Zigurd
There is good evidence that size is most things if not everything. We have big
brains, hence we have more intelligence than chimps. We cook our food, so we
don't spend all day feeding our big brains.

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ballard
Brain size is correlated to intelligence in humans by 0.35.

Cooking food is an adaptive behavior that reduces disease and alters
nutrition. It was the gradual exploitation of nature for the domestication of
monocultural, industrial agriculture with supply chain processing that makes
for most food modern people eat including "convenience" foods. This division
of labor, whether organic farmer or pseudo-family megafarm, is what renders
individual hunter-gathering a waste of time. From this over-abundance of
calories and protein, it could support more robust bodies and larger brains,
but it's a moot point considering obesity and the inevitability of the
technological singularity.

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ot
Regarding brain size, there is a very nice TED talk:

[http://www.ted.com/talks/suzana_herculano_houzel_what_is_so_...](http://www.ted.com/talks/suzana_herculano_houzel_what_is_so_special_about_the_human_brain.html)

The speaker argues that while there are animals with brains bigger than ours,
their neuron density is lower; overall, humans have the highest number of
neurons. She goes on by noting that the energy that the brain consumes depends
only on the number of neurons, not the size, thus making humans the species
that has the most energy-hungry brain. This leads to some interesting theories
on how the evolution of our brain is related to our nutrition habits, which I
found quite mindblowing.

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kahoon
A way to test this hypothesis: elephants and certain whales have bigger brains
than us. By the article's reasoning we should find mechanisms in these
animals' brain which prevents neurons from "untethering".

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bl
I like your gist of putting the hypothesis to test, but there are serious
practical factors that would prevent your proposed experiments. Small- and
medium-sized mammals (e.g., rodents and primates, respectively) are somewhat
convenient for experimenting in that they can be housed/fed humanely and fit
into an fMRI machine whose aperture is ~0.5 meters in diameter. I do not see
how one could reasonably do the same for elephants and whales.

But let's do a thought experiment and see if we can reasonably dispense with
the need for experiment itself. The article (via the researchers' statements)
zoomed past a detail: cortical surface area is much more indicative of neural
processing capability than gross brain volume. In many contexts, a
neuroscientist might use "brain size" as shorthand for cortical surface area.
Also consider that more "advanced" mammals tend to have more convoluted
cortexes, thus larger cortical surface areas. So it's quite possible for a
large mammal's (whale's or elephant's) brain to be volumetrically larger than
a human's, but to have relatively smaller surface area because it is less
convoluted.

In the event that we could actually accomplish such a comparative study as you
propose, we'd probably find that "tethering" does not monotonically increase
with surface area. Then we'd determine that the authors' hypothesis is overly
simplified.

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muloka
For those of you comparing animal brains to human brains and how it relates to
consciousness and intelligence take a look at the "Cambridge Declaration on
Consciousness." (signed on July 7, 2012)

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retr0h
... it's just how you use it

