I’m working on EEG source localization, but I’m encountering some challenges with coregistration. I don’t have MRI scans for my participants (29 in total), so I’m using the standard MNE sample MRI that comes with the mne toolbox. I do have 3D scans of the participants, from which I extracted the 3D positions of the electrodes.
When I try to line these 3D positions up with the sample MRI, I run into a problem. Im unable to fully line up the 3D positions with the MRI, since the shape of the MRI scan does not match the shape of the 3D positions. This results in that some electrodes appear to be floating above the scalp, leaving a gap between the electrode and MRI template. And also, a few electrodes end up inside the MRI scan. I have added a screenshot to make clear whats happening. I would like to use the result of the coregistration for the trans.fif file in the forward model.
How problematic are these alignment issues for my source reconstruction results? Will the gaps or misplaced electrodes affect the accuracy?
Are there any options or techniques to solve these alignment problems? Or would the option trans = ‘fsaverage’ be better to use for the forward modelling?
Thanks in advance for your help!
- MNE version: e.g. 1.8.0
- operating system: Windows 11