3dDeconvolve compare between contrasts [A1-B1 vs A2-B2]

Hello all,

I have a subject which we scanned twice and I would like to compare the experimental task (A) vs the control task (B) on day1 vs day2. So something like [A1-B1 vs A2-B2]. I’m not sure how to code that in 3dDeconvolve using the gltsym. I tried: A1 -B1 -A2 +B2 which seems odd.
But arithmetically it works, but I’d like to ensure the stats are also computed accordingly.


I tried: A1 -B1 -A2 +B2 which seems odd

It’s not odd at all. Instead, the expression basically tests the interaction between task and day.