Fig. 2.
Multidimensional scaling plots. These plots illustrate the correlation between Brodmann areas in resting-state data, before and after corpus callosum lesion (using averaged correlations for the three monkeys). (A and C) Prelesion and (B and D) postlesion (note that the data points in each pair of plots are identical). Each Brodmann region is represented by a dot (circles for LH and squares for RH). Dots are arranged (by MD scaling) such that the distance between each pair of dots is proportional to their dissimilarity (inverse correlation as defined in the main text). Therefore, dots that are closer together represent regions with stronger functional connectivity. In A and B, regions are colored by hemisphere (blue circles, LH; red squares, RH). Each region is linked to the mean position in the scaled (illustrated) space for its hemisphere; note that before the lesion, the networks for the two hemispheres are heavily overlapping, but after the lesion, they move apart. In C and D, the same data are presented as in A and B, but now each area is linked to its homotopic counterpart in the contralateral hemisphere, and areas are colored according to the within-hemisphere blocks (defined by k-means clustering; Materials and Methods). Note that before the lesion, there is strong pairwise organization with each pair of homotopic regions falling close together in scaled space; after the lesion, the pairs are separated.