[Mne_analysis] MRI coordinate to closest volume source point

[Marijn van Vliet]

        External Email - Use Caution        

Hello MNE community,

I've made a volume source space for the MNE-Somato dataset like so:


import mne
import mne_bids

bids_root = mne.datasets.somato.data_path()
subjects_dir = f'{bids_root}/derivatives/freesurfer/subjects'
trans = 
mne_bids.get_head_mri_trans(f'{bids_root}/sub-01/meg/sub-01_task-somato_meg.fif', 
bids_root)
bem = mne.make_bem_model('01', ico=4, subjects_dir=subjects_dir)
bem_sol = mne.make_bem_solution(bem)
src = mne.setup_volume_source_space(subject='01', bem=bem_sol, 
subjects_dir=subjects_dir)


How would I translate an MRI coordinate, lets say (x=33, y=8, z=57) to the 
nearest source point (="vertex") in the source space? Could someone explain a 
bit about the coordinate systems and transforms in play?

best,
Marijn.

-- 
Marijn van Vliet
Postdoctoral Researcher
Department of Neuroscience and Biomedical Engineering
Aalto University, Finland