Dear SPMers,
for 2nd level analysis, I set up a 2x3 flexible factor design, including the interaction terms between the within-factors A and B = A1B1 A1B2 A1B3 A2B1 A2B2 A2B3 and the subject terms (between) according to page 6 in the paper of Gläscher/Gitelman:
Design matrix = [ A1B1 A1B2 A1B3 A2B1 A2B2 A2B3 + 15 subject terms ]
I wonder whether the F contrast
1 0 -1
1 -1 0
0 1 -1
would answer the question in which voxel we observe a decrease of activation over time across the 3 time points (factor B) in condition A1?
I would be very grateful if anybody could help me with this.
Thank you very much.
Best wishes, Robert
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