Q: why eletrode positions plot is different from other tools like Fieldtrip?

[iraquitan]

In the Wikipedia 10–20 system (EEG) the electrode positions when plotting are much like the following image (EEG1010.lay) extracted from Fieldtrip, where the midline (T9 -- Cz -- T10) is definitely a straight line.

But in MNE when I plot the standard montage like the following:

import mne

montage = mne.channels.read_montage('standard_1020')
montage.plot()

I end up with this plot (standard_1020) where the (T9 -- Cz -- T10) line is curved down.

Why there's this difference? And there are any implications on topomap visualizations?

Thanks in advance!

[agramfort]

it seems like the outlines parameter from http://martinos.org/mne/ stable/generated/mne.Evoked.html#mne.Evoked.plot_topomap is not exposed in plot_montage we could add this yes...

[cbrnr]

I remember having discussed this before - wasn't it related to a transform from some coordinate space to another (based on the fiducials) that isn't done? I can't find the relevant issue though.

[larsoner]

Yes this is probably a dup of #3987