Question about 3dMVM specific contrast

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1

Hello!

I am doing a 2 (Group: dep & ctrl) x 2 (Time: Pre & Post) design with scanner a categorical covariate. I have copied the model I did below. If I also wanted to examine whether depprevpost was different than ctrlprevpost, how would I include that with the model I have provided below? Thank you!

3dMVM -prefix scanner -jobs 1
-mask minicolinmask+orig
-bsVars “grp+scanner”
-wsVars “time”
-num_glt 5
-gltLabel 1 dep_v_ctrl_pre -gltCode 1 ‘grp : 1dep -1ctrl time : 1pre’
-gltLabel 2 dep_v_ctrl_post -gltCode 2 'grp : 1dep -1ctrl time : 1post’
-gltLabel 3 dep_pre_v_post -gltCode 3 ‘time : 1pre -1post grp : 1dep’
-gltLabel 4 ctrl_pre_v_post -gltCode 4 'time : 1pre -1post grp : 1ctrl’
-gltLabel 5 grp_time_interaction -gltCode 5 ‘grp : 1dep -1ctrl time : 1pre -1post’ \

2

examine whether depprevpost was different than ctrlprevpost

Your last inference seems to be exactly what you’re looking for:

-gltLabel 5 grp_time_interaction -gltCode 5 ‘grp : 1dep -1ctrl time : 1pre -1post’ \

3

THANK YOU! I was thinking that might be but wasn’t sure