How to define spacing when computing source space?

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1

MNE version: 1.4.2
Operating system: Ubuntu 22.04.3

I have been assigned a task to compute LCMV beamforming on mixed sources. However, I cannot understand which type of spacing to choose when computing source space.

src = mne.setup_source_space(subject, spacing=“ico5”, add_dist=False, subjects_dir=subjects_dir)

My supervisor and me worked on a project where we always used spacing=oct6 with LCMV beamformer. But the script for mixed sources that I have been given uses oct5. And my colleagues who worked with the same data but differently used ico5. While the MNE website recommends oct6 for mixed sources (Compute MNE inverse solution on evoked data with a mixed source space — MNE 1.9.0 documentation).

I am a bit confused, I know there is information on the MNE website but it does not make it clearer for me which spacing I should use.

Thanks!

2

As a general rule, I think you want at least 4000 source points (counted across both hemispheres), but preferably a bit more. Sometimes there is a good reason to use very few points, like when you are writing an example script that just needs to run fast but is not meant to do a serious analysis.

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