Designing axons & dendrites
From Neuron (Sep 2), an interesting combination of mathematical analysis and proof with biology:
Synaptic Connectivity and Neuronal Morphology
Two Sides of the Same Coin
Dmitri B. Chklovskii
Neurons often possess elaborate axonal and dendritic arbors. Why do these arbors exist and what determines their form and dimensions? To answer these questions, I consider the wiring up of a large highly interconnected neuronal network, such as the cortical column. Implementation of such a network in the allotted volume requires all the salient features of neuronal morphology: the existence of branching dendrites and axons and the presence of dendritic spines. Therefore, the requirement of high interconnectivity is, in itself, sufficient to account for the existence of these features. Moreover, the actual lengths of axons and dendrites are close to the smallest possible length for a given interconnectivity, arguing that high interconnectivity is essential for cortical function.
Article Outline
Introduction
Results
Design I: Point-to-Point Axons
Design II: Branching Axons
Design III: Branching Axons and Dendrites
Design IV: Branching Axons and Spiny Dendrites
Proof of Design Optimality
Comparison with Experiment
Discussion
Acknowledgements
Appendix
Note Added in Proof
References