How to add position from EEG channel file

Discussions
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1

Hi All,
I'm working with 59 channel EEG. in the channel file, I only have the position of the x-axis and y-axis. I also need the z axis to view the electrode's position on scalp, but unfortunately it is not available in my dataset. Is there a solution to this issue?

Thank you.

2

Is the Subject using Default anatomy or the individual's anatomy?

3

yes, I use protocol's default anatomy

4

Then if your electrodes are named as in the international 10-20 system, you can add their locations with respect to the default anatomy as:

  1. Right-click on the Channel file > Add EEG positions > ICBM152 > Generic > ASA 10-20 94
  2. Check the location of the electrodes on the scalp:
    3.Right-click on the Channel file > Display sensors > EEG head

If further adjustment is needed (electrodes are not exactly on the scalp but a bit under of above) you can project them to the scalp surface: Right-click on the channel file > MRI registration > Edit and click on the button "Project electrodes on scalp surface (iconProjectElectrodes). More info in here:
https://neuroimage.usc.edu/brainstorm/Tutorials/Epilepsy#Register_electrodes_with_MRI