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Hello SPM users, I have three questions about 2nd level analysis in a 3-conditions event design that includes time derivatives and parametric modulators. I would like to compare activation or deactivation between groups in each condition. In the first level I calculated several t contrasts for each condition. For example, taking into account just the first condition I calculated four t tests: A) Condition 1 effect: [1 0 0 …] B) Cond 1 Time Derivative [0 1 0 0 …] C) Cond 1 Parametric modulator: [0 0 1 0 …] D) Cond 1 Parametric modulator time derivative: [0 0 0 1 …] I carried out a 2 (group) x 2 (Basis Functions) full factorial, in which I included just C and D contrasts images (con_00XX). My questions are: 1) Is it correct to use a full factorial in this case? 2) If the use of full factorial is right, should I include all type (A to D) of contrasts? 3) Should I calculate negative contrasts (-1 0 0 … and so on) and carry out another full factorial with them? Thank you for your help and kind regards, CP