Dear SPMers,
This is probably a silly question but I am not sure how to do this correctly.
I have three regions of interest ('A','B','C'). Two regions ('A' and 'B') show increased activation during my contrast of interest and one region ('C') shows decreased activation. I would like to put all three into a DCM analysis but need to extract the timeseries for each using the same contrast.
If all were activated during the contrast then I would normally extract for the T-contrast and adjust for the F-contrast (but this will not work for the deactivated region 'C').
So, for 'A' and 'B', can I simply extract for the F-contrast and adjust for the T-contrast for A and B. Then extract for the F-contrast and adjust for the negative T-contrast for C?
With thanks,
Tim
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