Resolution

[akim1]

What is the finest resolution a connectome can be constructed at given the technology available?

[michaelseung]

I had trouble finding this, so someone correct me if I'm wrong. As of now, the NIH's Human Connectome Project uses diffusion MRI, with 1.25 mm isotropic resolution. However, neuroscientists use better technology (i.e. Focused Ion Beam Scanning Electron Microscopes) to achieve brain images at 6 nm resolution, fine enough to see each neuron's synapses. While a connectome has not be constructed yet at this resolution, the NIH has future plans for it.

[kristinmg]

I've also been reading about this. I think the human connectome project uses three MR methods for generating the connectomes. 1) rfMRI (resting state functional MRI) 2) dMRI (diffusion MRI)
3) tfMRI (task based fMRI)

In this article (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3740184/) from 2013 it says that the fMRI images give a whole brain coverage with 2 mm isotropic resolution (in 0.7 seconds) and the dMRI data has a 1.25 mm isotropic resolution. Ongoing technical developments, aiming at higher resolution using a 7 Tesla magnetic field (instead of a 3 Tesla for the resolution mentioned above), are also described.

[jovo]

yup, the word connectome is used lots by different people. jeff lichtman wrote an article with the word 'projectome', somebody else wrote one with 'synaptome', both to help differentiate, both failed :( we do lots of work on connectomes using EM data, with ~ 4 nm axial resolution. magnetic resonance microscopy uses MRI to get around 100 micron resolution, which is also cool.