Importing channel locs

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1

Hello all,
I've just started using brainstorm for EEG analysis. A big thanks to the developers for the GUI and such detailed tutorials.

I've BrainVissionAnalyser file (.eeg), corresponding channel info (BrainAmp channels) shows channel coordinates as [0.00,0.00,0.00] for all the channels, as the .vhdr file has no information on that. However, a .txt file is provided with the dataset, which includes the coordinates of the channels. Also, I'm using the default anatomy provided within the brainstorm.

I was wondering if there is a way to import these coordinates from the text file itself. I know that I can manually enter the coordinates, but there should be an easier way.

Rajat

2

I was wondering if there is a way to import these coordinates from the text file itself.

Right-click on the channel file > Add EEG positions > Import from file.
As in the EEG/Epilepsy tutorial (which I recommend you follow before importing your own recordings):
https://neuroimage.usc.edu/brainstorm/Tutorials/Epilepsy#Prepare_the_channel_file

You would need to adjust the positions manually as there is almost no chance that your coordinates match the template in Brainstorm (rotation/translation/resize, then project on scalp) .

Also, I'm using the default anatomy provided within the brainstorm.

If this is a standard cap, with standard electrodes positions, you could then use one of the defaults available in the same menu (also in the menu "Add EEG positions").

If your text file contains real 3D coordinates digitized manually on the head of the subject, then you might be able to warp the template to match the real shape of the head:
https://neuroimage.usc.edu/brainstorm/Tutorials/TutWarping

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