when I study the Tutorial FemMedianNerve, I compute the DUNEuro DTI FEM head model of EEG as the Tutorial say. No errors were reported during the calculation. But when I export the head model to matlab, I find it strange that the first EEG row (EEG001 channel) of head model Gain Matrix is all zero. I don't think that's possible in practice. All the simnibs mesh and iso2mesh mesh meet this strange thing. why？
Hi there,
This is not an error but how the forward computation is designed.
The first electrode is defined to be the reference electrode, therefor it's set to zero.
Later in the Brainstorm inverse process the average reference is applied.
If you want to use this leadfield outside Brainstorm then you need to change the reference according to you application.
thank you, now I understand it.
Excuse me, when I study the Realistic head model: FEM with DUNEuro，what could be the reason that the leadfield I calculated from 1-66 and the last two rows are all empty?
Hello @whj, the Gain (or lead field) matrix of the head model model is NaN for the modalities that do not correspond to the modality that the head model was computed for.
You can check the modality for those channels within the Channel file.
Right-click on the Channel file then select Edit channel file, now you can check the modality (Type column) of each sensor.
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