Thanks. I see that now, I removed emotion from the "bsVars" but I still received the same exact error.
Also, is there a way to specify the within x between interaction in the model, or does it do that automatically?
for example, my main interaction of interest is Group (between ) x Age (between) x Emotion (within).
Is 3dMVM the best program for that, or should I use 3dLME?