Hi Ashkan,
With your design, I would create eight 3-column EVs, with each EV coding the duration of the 'C' events within their respective 'B' block.
i.e., Eight separate EVs for B1_C1; B1_C2; B2_C1; B2_C2; B3_C1; etc...
Then, I would code different contrasts for the effects that you're interested in.
B1_C1 - B1_C2: difference between C1 and C2 during B1 block
B2_C1 - B2_C2: difference between C1 and C2 during B2 block
(B1_C1-B1_C2)-(B2_C1-B2_C2): interaction of (C1-C2) difference as a function of block 1 versus block 2
: just to be clear, this contrast would be coded [+0.5, -0.5, -0.5, +0.5, 0, 0, 0, 0]
--Greg
____________________________________________________________________
Greg Burgess, Ph.D.
Staff Scientist, Human Connectome Project
Washington University School of Medicine
Department of Anatomy and Neurobiology
Phone: 314-362-7864
Email: [log in to unmask]
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