I can't import channel file correctly

Discussions
1

Hello all,

I want to use a .xyz file with electrodes coordinates in Brainstorm. The problem is that the electrodes coordinates I am using are not in the same coordinates system that Brainstorm uses. In Bainstorm’s tutorial said that all the surfaces, sensors and additional points are converted into Brainstorm’s system (SCS System) when they are imported in Brainstorm, so I figured I didn’t need to perform the transformation between systems. This didn’t work, so I don’t know what I should do.

Thank you,

Federico

2

Hi,

Maybe the tutorial is a bit misleading here because the registration is possible only if the channel location include some extra points corresponding to anatomical fiducials (such as the nasion and ear points; because they help define a coordinate system based on the subject’s head which can shared by the EEG/MEG channel locations and the MRI: this is explained in a new tutorial, http://neuroimage.usc.edu/brainstorm/CoordinateSystems), which is not your case. I therefore encourage you to give a try to the automatic and/or manual registration features available in BST.

Give a try to what’s described in http://neuroimage.usc.edu/brainstorm/Tutorials/TutImportAnatomy#Fix_registration_with_MRI under ‘Manual alignement’ and let me know how it goes

3
  1. Try to import your .xyz file with all the .xyz filters listed in the dialog window when you import you file, including the simple ASCII (.) file format
  2. For each one: check the result (right-click> MRI registration > Check)
  3. If none of those options work, your file format is not one of the .xyz supported formats (the extension does not necessarily defines a specific file format…) AND it is not in CTF/SCS coordinate system
  4. You only option is to edit it manually (right-click> MRI registration > Edit…)

Francois