Dear SPMers,
I have a question regarding EEG 3D source reconstruction.
I have 2 all ready averaged ERPs of 1s each. The pre-processing was done
using different software. I have processed them separately using the
BEM template and standard imaging. I now make a third dataset in which I
merge both ERPs. I define as contrasts [1 0] and [0 1]. I then process
the third dataset using the BEM template and standard imaging, because I
want the resulting images to be normalized to each other, so I can
compare the activity maps to each other.
How come I get different results for the contrast [1 0] than for the
first ERP? It is not just a scaling, there are different regions active.
I also get different results for the contrast [0 1] and the second ERP.
Can somebody please help me with this?
Best regards,
Pieter
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Pieter van Mierlo
Ghent University - ELIS
MEDISIP - IBBT - IBiTech
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