Fig. 4.

Support vector machine classification results for the comparison and discrimination between semantic variant PPA and nonfluent/agrammatic variant PPA. Top left: VBM results for the comparison between semantic variant PPA (svPPA) and nonfluent/agrammatic variant PPA (nfvPPA) (svPPA < nfvPPA green, nfvPPA < svPPA red, family-wise error corrected p < 0.05). Bottom left: Regions of interest (ROIs) based on independent meta-analyses. Right: Results of support vector machine (SVM) classification. Top: Regions most relevant for classification as svPPA in yellow, nfvPPA in light green. Note that the scale of the distance weights has no applicable units. Bottom: Sensitivity, specificity, and accuracy for the ROI approach and the whole brain approach in SVM classification.