Contact location after MNI normalization

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Dear Francois,

I have a question about contact locations after MNI normalization in Brainstorm:

To display MNI coordinates of single electrodes I worked with: right-click on Implantation-SEEG > File > Export to file > save as data type EEG: ASCII: Name,XYZ (*.txt).

Unfortunately I noticed that exported MNI coordinates are incorrect and shifted or even located outside the default anatomy brain.

I wondered why this is the case and I think it might be due to the fact that we performed the MNI normalization step at a later time point than described in the brainstorm tutorial: After importing the anatomy, manual determination of the fiducial points, the electrode position was constructed. Only then the MNI normalization was computed.

Do you have a suggestion how the MNI transformation can be recalculated afterwards for the electrode localization in order to get correct MNI localizations?

Thanks in advance for a suggestion!

Caroline

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What you describe here exports the contents of the channel file, which is the coordinates of the sensors in SCS coordinates:
https://neuroimage.usc.edu/brainstorm/CoordinateSystems

If you want to get the MNI coordinates of the sensors, select one of the file formats with "XYZ_MNI".

Or check our this new feature I've finally pushed yesterday:
https://neuroimage.usc.edu/brainstorm/Tutorials/Epileptogenicity#Anatomical_labelling
https://neuroimage.usc.edu/brainstorm/Tutorials/ECoG#Anatomical_labelling