Comparative Analysis of the Macroscale Structural Connectivity in the Macaque and Human Brain
Figure 5
Rich club structure in the macaque and human brain.
A. The normalized RCC suggests the presence of a rich club organization in both the human and macaque brains. For the unormalized curves see Fig. S3. The RCC obtained within the rich club regime (>1) were significantly higher than the ones obtained from random networks matched for node, edge and degree distribution (p<0.0001). B. Network and anatomical representation of the regions corresponding to the peak of the normalized RCC which is marked with a diamond in panel A (k = 56 for macaque and k = 55 for human). In the network representation, green and blue nodes represent rich club and non-rich club regions at level k respectively. Only connections involving at least one rich club region are depicted. The anatomical representation depicts the regions constituting the rich club on the inflated fiducials of both hemispheres of the brains of the two species. The spheres represent the centre of mass of the regions. Note the convergence of the rich club analysis to a highly overlapping set of regions in the two species. C. The observed overlap is significant within a range of the rich club regime. The significance was established by drawing randomly from a uniform distribution a number of regions from the MC and HC equal to the number of regions corresponding at each level k for the MC and HC separately. The procedure was repeated 10000 times and the overlap of these randomly drawn regions was computed forming a null distribution with which the original overlap values were compared.