Dear Alfonso and CONN forum,

I am running exploratory PPI analyses to inform SPM-based ROI multiple regression analyses. I want to recreate the ROI SPM model at the second level so I input the 10 covariates of no interest, two main effects, and their interaction. But I want to look at gender differences for the main effect of A, the main effect of B, and their interaction C but am unsure if I can do that all in one contrast or if I have to run three separately.

1) Am I correct that I first would select the 10 covariates of no interest,  main effects A and B, their interaction, male and female?

2) Then if I want to look at general model differences between males and females do I create a contrast such as [0 0 0 0 0 0 0 0 0 0 0 0 0 1 ; 0 0 0 0 0 0 0 0 0 0 0 0 0 -1]?

3) But if i want to look at gender differences for the main effect of A but control for all the other variables, I'm unsure how to enter the contrasts.

Help would be very much appreciated

Best wishes,
Erin