100-hour MRI captures the most detailed view yet of a whole human brain | Hacker News Reader

100-hour MRI captures the most detailed view yet of a whole human brain

sciencenews.org

58 pointshoward94112 comments

For those wondering how somebody sits still for 100 hours in an MRI, the answer is contained in the word "postmortem" in the subhead.

This isn't functional MRI, which observes the brain as it's working. This is a very high resolution static picture at a tens-of-microns scale. Assuredly very useful, but different from fMRI, which is what I first associate when somebody says "MRI" and "brain".

>fMRI, which is what I first associate when somebody says "MRI" and "brain".

That's an odd first-association. fMRI is not used much outside the brain, but neuroimaging relies on structural contrasts (i.e. "normal" MRI) and diffusion imaging (a proxy for looking at axonal connectivity) just as much as on functional ones.

I wonder if any patients in coma's were considered. I'd think it would be tremendously valuable to compare the difference between a living and a 'dead' brain.

*This might get into philosophical realm of brain dead vs alive. I'm just talking about 'active blood flow' and let the additional nuance about the other things be worried about by somebody who isn't me.

They’re still breathing which means they move.

Even the movement of blood through the brain can cause blur at this scale. The person needs to be very dead for this to work.

The breakthrough is the MRI system itself with this particular scan demonstrating an enormous new potential. The underlying research paper is at https://www.biorxiv.org/content/10.1101/649822v1

Is not 0.1 mm too coarse? Neurons are much smaller. Also, I wonder what is the black hole in the middle of the left image?

I believe that dark area is the corpus callosum (https://en.wikipedia.org/wiki/Corpus_callosum) -- bundle of nerve fibers that connects the two hemispheres of the brain.

That is above/around the black area. The black area is the lateral ventricle. It normally contains cerebrospinal fluid, however on the image it is empty.

The "hole" is a part of the ventricular system that produces cerebro-spinal fluid that circulates within the brain and spinal cord.

https://en.wikipedia.org/wiki/Ventricular_system

Here is one from a living person with 0.25mm resolution (data is also available to download) https://www.nature.com/articles/sdata201732

Scan time here is 53 minutes.

The average human brain is 1450 cubic centimeters. With a resolution of 0.1 millimeters, that's 100 * 100 * 100 data points in a cubic centimeter. For approximately 1.45 billion data points for one brain!

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