[Simnibs-discuss] Differences in Efield depending on Processing

[Joel Upston]

Hi there,

I have noticed a systematic difference between the two different lines of simulating the same currents, electrodes and underlying dataset. One is through processing through the leadfield and using only the electrodes and currents as given and the other is through only modeling those electrodes and currents without the leadfield. Now the 2nd pathway (no leadfield) is giving higher E_mag than the leadfield version (~7-12%), the spatial maps look similar but just the intensity differences. I think it has to do with the scaling that is done after the solve by scaling the estimated current calibration error, which if I understand correctly isn't done in the leadfield processing.  If this is the case I am trying to establish which would be more accurate to use in your view if I need a specific target value of (0.3 V/m for example). I have attached an image of a case where this is shown with the leadfield processed is on the left and the non-leadfield is on the right. I have tried this on about 5 different datasets and the pattern is consistent.

Thanks,

Joel
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