[link] The World's Most Powerful MRI Takes Shape

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http://spectrum.ieee.org/biomedical/imaging/the-worlds-most-powerful-mri-takes-shape

Standard hospital scanners have a spatial resolution of about 1 millimeter, covering about 10 000 neurons, and a time resolution of about a second. The INUMAC will be able to image an area of about 0.1 mm, or 1000 neurons, and see changes occurring as fast as one-tenth of a second, according to Pierre Védrine, director of the project at the French Alternative Energies and Atomic Energy Commission, in Paris

http://spectrum.ieee.org/biomedical/imaging/the-worlds-most-powerful-mri-takes-shape

Standard hospital scanners have a spatial resolution of about 1 millimeter, covering about 10 000 neurons, and a time resolution of about a second. The INUMAC will be able to image an area of about 0.1 mm, or 1000 neurons, and see changes occurring as fast as one-tenth of a second, according to Pierre Védrine, director of the project at the French Alternative Energies and Atomic Energy Commission, in Paris

Disclaimer: I'm a graduate student in medical imaging -- but not on the hardware side of things, so my remarks in these areas are likely to be incorrect.

I'm sure some are reading this hoping for applications to uploading (as the comparison to neurons is compelling), but IMHO (emphasis on humble) I don't expect MRI to be the path to nondestructive human brain imaging.

Problems:

Increasing the strength of the magnetic field is an easy way to increase resolution, but there are hard limits as to how much magnetic field a human brain can take. Already at 2 Tesla an MRI can heat and sometimes burn patients; the risk at 11.75 Tesla (as in the article) is proportionally greater.
Not all brain-related information that may be necessary for reconstruction is visible to an MRI, e.g., some kinds of neurotransmitters.
MRI resolution can be high, but contrast can be low -- particularly for those applications to sodium and potassium nuclear resonance the article briefly mentions. You can improve contrast by injecting contrast agents, but this also comes with safety risks, and the blood-brain barrier makes it difficult to chose good contrast agents.
Increased resolution implies increased acquisition time, and increases in acquisition time imply increased artifacts from motion blurring. In the early days of MRI they used to sedate or briefly kill patients to obtain decent imagery, so this problem is not insurmountable.

For a while, at least, destructive imaging is going to be my best bet for uploading.

EDIT: Removed some confused remarks in 4.

As passive_fist already covered, the strength of the magnetic field is mostly irrelevant in terms of safety. The human brain doesn't suddenly stop functioning at 11 Tesla, nor does it get heated by the static magnetic field. Radiofrequency heating safety at high field is still an ongoing topic of discussion, but it should (presumably) not be insurmountable problem, and there are technologies in development that may reduce the required RF power substantially.

The bigger question, assuming you were being serious with your reference to uploading, is what MRI c... (read more)

22gwern13y

("briefly kill"?)

9passive_fist13y

A stationary magnetic field cannot heat and burn patients. What you are referring to is radio frequency heating, caused not by the magnetic field but by the radio waves used to do the actual probing. You do not need to increase the RF power to make use of the increased resolution offered by higher magnetic fields.