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Hi Sanne, There is no way to get a cluster-level p-value at the moment. If that's what you absolutely need, it's simply not possible to do directly or with simple steps. Surely you could trick randomise, save all possible permutations, convert the stat to a p-value, take the minimum of each, then convert to a z-score, compute the cluster sizes for each permutation, build a null distribution of the largest cluster size, then confront the result without permutation to that null, etc... Not only this will require a lot of work, but it also requires that the set of permutations needed to test both contrasts overlap with each other. This is trivial if they are both continuous regressors, but if both are discrete, and perhaps orthogonal, even what I just described becomes impossible. So... no cluster-level p-values for the intersection of contrasts (by intersection I mean binarise both and multiply one by another, i.e., the overlap). Regarding the z-max, the image was binarised, so it's all 0 and 1. All the best, Anderson On 4 June 2014 16:11, Sanne Detiger <[log in to unmask]> wrote: > Hi Anderson, > > Thanks again for your quick response. I'm a bit puzzled about what you > mean with 'compute the intersect'. Could you eleborate on that? > I have another question about my cluster output. My Zmax is 1 in every > cluster. Should this be the case, and what does it mean? > > Thanks in advance, > > Sanne > >