I am working on putting MEG data in source space. How do I go about making
all sources 'the same'. For example, if I perform MNE for subject A using
their fmri structural and the same with subject B then the actual 'source
points' across subjects don't necessarily correspond to one another.
I'd like to convert these source spaces to a common default space so that
the source points are common across people
You can morph one participant's source space to another source space (which
could be a different participant, an average brain created by averaging all
your MRIs, or even a separate average brain such as 'fsaverage' which comes
with Freesurfer). See this chapter from the MNE handbook
<http://martinos.org/mne/stable/manual/morph.html> for how to do it in the
bash version of MNE, or this example
<http://martinos.org/mne/stable/auto_examples/inverse/plot_morph_data.html>
for Python code.
Thank you both for your replies. I am aware that I can morph one subject to
another. What I was wondering if there was some 'default' space that I can
specify so that the space isn't dependent on any of my subjects
In that case I might recommend fsaverage (which should be somewhere in your
Freesurfer root directory). There may be other popular default spaces as
well, but this is the one I see used the most.