Zealousideal-Alarm37 OP t1_jegvrv1 wrote on March 31, 2023 at 10:44 PM

Reply to comment by Brain_Hawk in If MRI Voxels are 1mm^3 how can MRIs identify something as thin as white matter? by Zealousideal-Alarm37

My issue with this explanation is that techniques like diffusion tensor imaging (a form of dMRI) can map paths taken in the white matter (ie the actually axons of neurons, and the myelin on this axons that make white matter white in the first place). Axons are very thin iirc, and while the cortex is thicker than the resolution of the MRI, how can it map things smaller than that resolution?

Do Voxels overlap?

Brain_Hawk t1_jeh46nf wrote on March 31, 2023 at 11:48 PM

Dti does not measure axons.

It makes a model of white matter tracts based on the characteristics os the direction of diffusion. Like so many things MRI, it's a model, and an estimate of how large bundles of axons are organized and traverse through the WM.

If you wanna learn more I bet you can find some good videos on YouTube. :)