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Andy, > If I got this activation results, p (unc) set as 0.05 (is this setting > voxel level?) then I got a cluster FWEp = 0.051, is it reportable? If it > is FWEp < 0.05 but under this p threshold setting, is it significant?? it is important to understand and make a clear distinction about voxel-level and cluster-based thresholding. The voxel-level thresholding comes first, and on this data, you can perform cluster-level correction. As mentioned in the past, there is nothing magical about 0.05, so if you had good reasons to expect a cluster in this very location, you could still report it truthfully as just not being significant, but plausible. Further analyses may be required to support that claim, though. Having said that, your threshold at the voxel level is 0.05 uncorrected, corresponding to a t-value of 1.7, which is very, very low (i.e., liberal), given the massive number of multiple comparisons a typical imaging study entails (SPM expects almost 40 clusters by chance at this level). This cluster is large, and the data seems to be quite smooth, which further argues against the cluster's credibility. I would therefore not be overly optimistic that this is not chance, and would not expect it to pass rigorous inspection. But without knowing much more about this dataset, it is hard to be definitive. Cheers, Marko -- ____________________________________________________ PD Dr. med. Marko Wilke Facharzt für Kinder- und Jugendmedizin Leiter, Experimentelle Pädiatrische Neurobildgebung Universitäts-Kinderklinik Abt. III (Neuropädiatrie) Marko Wilke, MD, PhD Pediatrician Head, Experimental Pediatric Neuroimaging University Children's Hospital Dept. III (Pediatric Neurology) Hoppe-Seyler-Str. 1 D - 72076 Tübingen, Germany Tel. +49 7071 29-83416 Fax +49 7071 29-5473 [log in to unmask] http://www.medizin.uni-tuebingen.de/kinder/epn/ ____________________________________________________