What are the grey gaps on the sLORETA brain scout map?

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Hi everyone,

I am wondering if anyone knows what the grey gaps are in the brain scout map are?

In my methods, I used scalp EEG data, which I pre-processed on Brainstorm. I used the ICBM MRI template, warped my eeg sensors, applied notch, bandpass filters, removed artefacts etc.
Then, I created a headmodel "Open MEEG BEM" and used sLORETA for source localisation. When I open the sLORETA: EEG(Constr) and select "laus60" I get the following brain scout image (see attached).

(1) Does this mean the signal from the grey areas is not included in my analysis because Lausanne parcellations do not capture the full cortical regions?
or, (2) is this an illustration issue? the regions are being fully captured but the parcellation is trying to visually define the individual segments in one region ie: superior temporal region is split into superiortemporal1, superiortemporal2, superiortemporal3, superiortemporal4,... and so on. (the effect is worse as the parcellation number goes up)

Thank you!

Screenshot 2024-07-04 at 15.17.41
Screenshot 2024-07-04 at 15.17.411822×1206 109 KB

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Those are spaces between vertices. They are portrayed like that as Scouts are defined only for vertices, so the inter-space between scouts has no color. You can see this in detail by showing the edges between vertices (Edge button on the Surface tab).

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Activity is computed per vertex, and there are no vertices there, these are only the edges.
When the activity is plotted, although it is defined per vertex, its values are interpolated on the surface. Note that this interpolation is not done with Scouts, thus the gaps.

Yes, the activity is considered for the parcellations a.k.a Scout as they consist of sets of Scouts