Rapid Conduction and the Evolution of Giant Axons and Myelinated Fibers

@article{Hartline2007RapidCA,
  title={Rapid Conduction and the Evolution of Giant Axons and Myelinated Fibers},
  author={Daniel K. Hartline and David R. Colman},
  journal={Current Biology},
  year={2007},
  volume={17},
  pages={R29-R35}
}
Nervous systems have evolved two basic mechanisms for increasing the conduction speed of the electrical impulse. The first is through axon gigantism: using axons several times larger in diameter than the norm for other large axons, as for example in the well-known case of the squid giant axon. The second is through encasing axons in helical or concentrically wrapped multilamellar sheets of insulating plasma membrane--the myelin sheath. Each mechanism, alone or in combination, is employed in… Expand
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