Scaling Theory in Axons and Dendrites

Neurons, the fundamental cellular units of the nervous system, have complex branching processes that connect to one another. A neuronal network, much like the cardiovascular system, is a resource distribution network subject to biophysical constraints. Previous work has focused on deriving power laws that illustrate the relationship between geometric scaling of cardiovascular vessel length and radius and fluid flow, space-filling, and whole organism metabolism. Here, we explore the possibility of extending this theoretical framework to analyze structural properties of neurons, aiming to understand the relationship between neuron structure and function. We test theoretical predictions against scaling ratios extracted from image data. We find that the distributions of scaling ratios in neuron processes across brain regions and species are nearly identical to those observed in cardiovascular networks, supporting the notion that a unifying framework underlies these diverse biological systems.