  The human braingraph, or connectome is a description of the connections of
the brain: the nodes of the graph correspond to small areas of the gray matter,
and two nodes are connected by an edge if a diffusion MRI-based workflow finds
fibers between those brain areas. We have constructed 1015-vertex graphs from
the diffusion MRI brain images of 395 human subjects and compared the
individual graphs with respect to several different areas of the brain. The
inter-individual variability of the graphs within different brain regions was
discovered and described. We have found that the frontal and the limbic lobes
are more conservative, while the edges in the temporal and occipital lobes are
more diverse. Interestingly, a "hybrid" conservative and diverse distribution
was found in the paracentral lobule and the fusiform gyrus. Smaller cortical
areas were also evaluated: precentral gyri were found to be more conservative,
and the postcentral and the superior temporal gyri to be very diverse.
