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Hi all: I have a quick PPI question. I am creating PPIs from a contrast where Condition 1 > Condition 2 + Condition 3. For this, I used contrast weights of 1, -.5, -.5 when creating the PPI from the VOI. When the PPI is created, and the three graphs are printed (hemodynamic and neuronal response, convolved psych variable, and PPI) I notice that up at the top, next to the "Factors" prompt, I see that the listed factors have weights of 1, -0, and -0, respectively. Does this mean that SPM defaulted those -.5 weights to 0? I wonder because when I look at the convolved psych variable graph, it appears that the contrast weights conform to a 1, -.5 -.5 structure. Any insight on this would be appreciated. Thanks.