Dear SPMers,
I am performing EEG source localisation using the batch tool. We did not measure electrode positions or MRIs so I'm relying on the defaults (61 scalp electrodes, extended 10-20 system). However, the main source I have estimated for a well-known ERP (the P2 peak of the laser-evoked potential) is too deep in the brain by at least 2-4cm, appearing in the corpus callosum when it should be in the mid/posterior cingulate. My guess is that there is an issue with the electrode positions, because the way we position our caps appears different to how the electrodes are positioned in MNI space according to the images created by SPM. SPM appears to automatically create coordinates in MNI space. Is there a way to manually adjust the way this step is performed?
Many thanks,
Chris
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