**D. Papo**, J.M. Buldú, S. Boccaletti and E.T. Bullmore^{}

*Philosophical Transactions of the Royal Society B*, **369**:20130520 (2014).

Complex network theory is a statistical physics understanding of graph theory, itself a much older branch of pure mathematics. The statistical physics approach aims at explaining observable macroscopic behaviour of a given system as emerging in a non-trivial way from the interactions of a vast number of microscopic units or agents. Complex network theory can be thought of as a subfield of statistical physics for structurally disordered, dynamically heterogeneous systems with non-trivial topology; and as an extension of graph theory to systems with high structural heterogeneity and inherently dynamical properties, two key properties of the vast majority of real-life systems, including brains.

Can this approach be useful when studying brain anatomy and function?

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