Branching Law for Axons
نویسندگان
چکیده
What determines the caliber of axonal branches? We pursue the hypothesis that the axonal caliber has evolved to minimize signal propagation delays, while keeping arbor volume to a minimum. We show that for a general cost function the optimal diameters of mother 0 d and daughter 1 2 , d d branches at a bifurcation obey a branching law: 2 2 2 0 1 2 d d d Q Q Q . The derivation relies on the fact that the conduction speed scales with the axon diameter to the power Q ( 1 Q for myelinated axons and 0.5 Q for nonmyelinated axons). We test the branching law on the available experimental data and find a reasonable agreement.
منابع مشابه
Hypothesis Branching Law for Axons
Background: Axon diameters vary widely among different animals, neuron classes and even within the same neuron. What determines the caliber of axonal branches? Presentation of the Hypothesis: We pursue the hypothesis that the axonal caliber has evolved to minimize signal propagation delays, while keeping arbor volume to a minimum. We show that for a general cost function the optimal diameters o...
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