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1

Hi,

According to the MNE cookbook (
http://martinos.org/mne/manual/cookbook.html#computing-the-forward-solution),
the --mindist option may be employed during computation of the fwd solution
and suitable values for this option are "of the order of the size of the
triangles on the inner skull surface."

Where should I look to find out the size of these triangles in my data? I
used "mne_watershed_bem --atlas" to create my BEM mesh. Thank you for any
help you can offer.

Best wishes,

Vincent
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2

hi Vincent,

here is a tiny python script to address your question:

https://gist.github.com/agramfort/5244414

The output is:

head 0.00721512121192
skull 0.0057216261293
brain 0.00540786011339

so the average distance between nodes is 5mm for skull and brain
surfaces and 7 for the skin
if you use the default BEM models with 5120 nodes per layer.

That explains you why you have the --mindist 5 in the sample data demo script:

https://github.com/mne-tools/mne-scripts/blob/master/sample-data/run_meg_tutorial.sh#L73

HTH,
Alex