Hi SPM'rs,
I'm new to SPM and despite reading the manual and several tutorials/forums, I'm still unclear on how to generate the correct design matrix and contrasts for the following experiment I'm working on.
It's a 2x3 design: 2 groups (patients v controls) have scans under three drug conditions (D1, D2, placebo). The scan is an emotional faces paradigm with three conditions; shapes, angry faces and fearful faces.
So far, I have conducted the first-level analyses on each scan and generated contrast files for anger > shapes, shapes > anger, fearful > shapes, shapes > fearful ... etc.
I've also run a two sample t-test on the placebo scans (patients v controls).
But I get stuck with the interaction analysis. I want to run a 2X3 factorial repeated measures ANOVA and examine main effects of group and drug AND the interactions.
If someone could advice on the correct set up of the model and the contrasts used to examine main effects and interactions, I would be very grateful.
All the best,
James.
|