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all amount of each tissue class after normalisation. Images were smoothed with a 6 mm full width at half maximum Gaussian kernel. The outputs of this procedure were the population templates of GM and the deformation parameters of each individual to this template. The deformation parameters were then used to generate the modulated and normalized GM maps, which are in a standard space, and to conserve global GM volumes. The input features for the subsequent analysis were the smoothed modulated normalized GM images. Given the very high order Integrin Antagonist 1 (hydrochloride) dimensionality of the VBM output and the expectation that only a few of these features would be meaningful for prediction, we applied a further feature selection step. We used whole-brain ANOVA filtering to select the areas of maximum group differences between patients and controls. First the t-value and degrees of freedom were estimated for each voxel in the training set. Then the t-map was converted into a p-map, and voxels higher than the threshold were masked out and discarded for classification purposes. Support vector machine is a supervised, multivariate classification method with optimal empirical performance in many classification settings that has previously been utilized in neuroimaging research. Supervised refers to the training step in which the differences between the groups to be classified are learned. With structural MRI data, individual images are treated as points located in a high dimensional space, defined by the GM voxel values of the ANOVA-thresholded maps. A linear decision boundary in this high dimensional space is defined by a hyperplane, and SVM finds the hyperplane that maximizes the margin between two training groups, i.e. the separation between the training subjects that are most ambiguous and difficult to classify. In the SVM classification, the whole multivariate VBM pattern over the set of thresholded areas jointly Quercitrin generated the significant classification results, and the significance of such results therefore refers to the whole pattern. To examine whether the SVM classifier could be expected to predict diagnosis or prognosis in new patients, we trained the model with leave-one-out cross validation. For each cross validation iteration, the data were

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