# mne.coreg.get_mni_fiducials¶

mne.coreg.get_mni_fiducials(subject, subjects_dir=None, verbose=None)[source]

Estimate fiducials for a subject.

Parameters
subjectstr

Name of the mri subject

subjects_dir

Override the SUBJECTS_DIR environment variable (sys.environ[‘SUBJECTS_DIR’])

verbose

If not None, override default verbose level (see mne.verbose() and Logging documentation for more). If used, it should be passed as a keyword-argument only.

Returns
fids_mrilist

List of estimated fiducials (each point in a dict), in the order LPA, nasion, RPA.

Notes

This takes the fsaverage-fiducials.fif file included with MNE—which contain the LPA, nasion, and RPA for the fsaverage subject—and transforms them to the given FreeSurfer subject’s MRI space. The MRI of fsaverage is already in MNI Talairach space, so applying the inverse of the given subject’s MNI Talairach affine transformation ($SUBJECTS_DIR/$SUBJECT/mri/transforms/talairach.xfm) is used to estimate the subject’s fiducial locations.

For more details about the coordinate systems and transformations involved, see https://surfer.nmr.mgh.harvard.edu/fswiki/CoordinateSystems and Source alignment and coordinate frames.