Self-similarity logic: a common pattern in the vascular and nervous systems

Vascular and neuronal networks are examples of body structures created by processes of branching morphogenesis, showing a similar architecture. Like vascular network morphogenesis, where morphology adapts to the amount of flow, neuronal branching dynamics also can be modulated by neural activity. Axon branching, indeed, often occurs as a dynamic process that involves branch addition and branch retraction. Self-similarity logic characterizes both the nervous and the vascular system. From a morphologic point of view, the self-similarity of the vascular system is straightforward, being the result of a hierarchical sequence of bifurcations, leading to a structure which can be considered strictly self-similar.