Comparison and convergence of multiple group analyses. We compared voxel-based and non voxel-based group analyses for three contrasts and displayed results for the left hemisphere (one individual left sagital slice): right motor activation (first row), reading-related activation (second raw) and left calculation network (third raw). a) RFX map thresholded at Z > 4. b) Overlap of individual statistical maps thresholded each at p < 10-2 uncorrected. Color scale ranges from 10% to 30% overlap. c) Brain functional landmarks of the group, plotted on an inflated human template brain (with Caret software http://brainmap.wustl.edu/caret, Van Essen et al., 2001). Color code is used to mark all individual maxima corresponding to one functional area identified in the RFX analysis. Motor activation; yellow = central sulcus. Reading; yellow = precentral gyrus, purple = inf. frontal gyrus, light green = mid. temporal sulcus, dark green = sup. temporal sulcus, red = fusiform gyrus. Calculation; yellow = precentral gyrus, purple = mid. frontal gyrus, red = intraparietal sulcus, blue = sup. occipital gyrus, light green = inf. temporal gyrus. Number of subjects correspond to the number of BFLs with a p < 10-2. d) Parcel-based RFX map thresholded at Z > 5. Largest significances for each contrast are colored in yellow (coordinates of each cerebral area correspond to the centre of the most significantly activated local parcel). (abbreviation: ips = intraparietal sulcus, oper. = pars opercularis of inf. frontal cortex, tri. = pars triangularis of inf. frontal cortex).