
Mapping the Brain at High Resolution - ArtWomb
http://news.mit.edu/2019/mapping-brain-high-resolution-0117
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est31
Their resolution is 60 x 60 x 90 nm which is far below the 20 um that BigBrain
used in 2013 for their whole-brain scan [1].

Especially, axons are 0.2-20 um in diameter. With a resolution of 20 um you
won't really find them, but with 0.01 um, you will certainly be able to
identify them. This could lead to new anatomical insights _in human brains_. I
remember recently someone complaining on hn that a new finding about a
connection of two brain regions in mice hasn't been confirmed in humans yet
[2]. If scans of entire human brains at 0.01 um resolutions were available,
you could verify claims like these by just checking the data.

Edit: corrected the BigBrain resolution.

[1]:
[https://en.wikipedia.org/wiki/BigBrain](https://en.wikipedia.org/wiki/BigBrain)

[2]:
[https://news.ycombinator.com/item?id=18943385](https://news.ycombinator.com/item?id=18943385)

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SubiculumCode
The Wikipedia link for BigBrain you provided lists the resolution at 20 µm
isotropic 3D voxels. That is ~2.71 µm in each direction.

~~~
est31
Nope. Yes, the Wikipedia link says 20 um isotropic resolution, but that means
20 um per direction. 20 um is a unit of length, while 20 um ^ 3, a unit of
volume. If it were about volume, you'd be correct.

Also, I just looked at the paper [1] and here it says:

> To generate a data set with isotropic resolution, we down-scaled all images
> to 20 µm by 20 µm to match the section thickness of 20 µm.

So that confirms the 20 um per direction, no?

Edit: oh no, I just see that I wrote 1 um above, not 20. Not that 2.71 is
correct but I guess that's what confused you. Corrected. Thanks!

[1]:
[http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.899...](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.899.2730&rep=rep1&type=pdf)

~~~
SubiculumCode
<slaps forehead> You are right about the resolution. Apparently I did not have
my coffee because I work with voxels all the time.

~~~
est31
It's all good :)

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joe_the_user
I can't figure out what is meant by "expand" in this and other quotes:

"The new technology combines a method for _expanding_ brain tissue, making it
possible to image at higher resolution, with a rapid 3-D microscopy technique
known as lattice light-sheet microscopy. In a paper appearing in Science Jan.
17, the researchers showed that they could use these techniques to image the
entire fruit fly brain, as well as large sections of the mouse brain, much
faster than has previously been possible."

\--> I mean, are they pumping the tissue up like a balloon or what?

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DoctorOetker
[https://en.wikipedia.org/wiki/Expansion_microscopy](https://en.wikipedia.org/wiki/Expansion_microscopy)

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peter303
Considering all 302 nerouns and 7000 synapses in c. elegans has been known for
a decade. But how this maps into c. elegans behavior is not understood.

Multiply this by a hundred million to get mammalian complexity

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kkylin
Not only that, the entire organism is only about 1000 cells. (Source:
[https://en.wikipedia.org/wiki/Caenorhabditis_elegans](https://en.wikipedia.org/wiki/Caenorhabditis_elegans))

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est31
Link to paper:
[https://kirchhausen.hms.harvard.edu/sites/kirchhausen.hms.ha...](https://kirchhausen.hms.harvard.edu/sites/kirchhausen.hms.harvard.edu/files/publication-
attachments/374140.full_.pdf)

