Brain Anatomy and Small-World Networks

Abstract

Network analysis of neural and other information-processing systems has recently provided unique insights into the large-scale cohesive organization of subcomponents at many scales of space and time. In this chapter, we describe the network analysis of neural systems in general and that of the healthy and diseased human brain in particular. We present evidence from a variety of species and data modalities that neural systems show the so-called ”small-world” network phenomenon which also ubiquitously characterizes social groups, scientific collaborations, the world wide web, transportation networks, power grids, etc. We attempt to provide reasons why this property might have been selected in brain evolution, and to explain its functional significance, while delineating the methodological intricacies of network analysis of neuroimaging data.

Keywords: Network construction, scale-free, exponential, power law, human, monkey, cortical thickness, degree distribution, small world, modularity, tractography.