Hi Francois,
I have followed every step according to what you have suggested so far and what is mentioned in the tutorials but I am still getting predominant basal activation.
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To start with, I linked the AUX file and did the spectral evaluation to remove 50Hz harmonics, mark some bad channels and segments.
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Manually marked eye blinks, saccades and heart beats across all trials.
Computed the SSPs according to the SSP tutorial. Cardiac first, blinks later and then a generic SSP for saccades.
All the major components are 12%, 19% and 18% respectively. Specifically for saccades if I add a filter of 1Hz-2.5Hz the component weight increases upto 31% but that affects the p3 amplitude greatly. So I resorted to the 18% component. For blinks and saccades the sensor cap shows a strong dipolar pattern for frontal regions. -
The averaged waveforms for deviant & standard
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Source space (dSPM) averages for deviant and standard
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MRI Co-reg for your reference
Since you got good localisation for N100, I am quite sure I have made a mistake somewhere but can't seem to isolate that.
Please let me know.
Best,
Kanad