Dear SPMers,

I would like to ask for advice regarding the appropriate 1st level t-contrast. The resulting con_XXX.imgs should be suitable to be taken to a 2nd level model. If I would like to test for the effect of a factor with 2 levels (first column representing first level, second column representing second level of the factor) on the second level (group-level), would it be appropriate to use the following contrasts on the first level t=[1 0] and t=[0 1]? Or would it be t=[1 -1] and t=[-1 1]? 

Best,
Jokel