Limitations of approximate solutions for computing the extracellular potential of single fibers and bundle equivalents.


Journal Article

The mathematical description of the extracellular field generated by activity in an excitable fiber in an unbounded volume conductor will depend on assumptions made about the sources and the source-field relationship. This paper examines and compares the rigorous and conventional approximate solutions of Laplace's equation used to evaluate the extracellular potential of a single, cylindrical fiber. The single fiber is considered as both a prototypical element (such as a nerve or muscle fiber) and an elementary model of an entire multicellular preparation (e.g., nerve bundle or Purkinje strand). The effects of the fiber radius, the intracellular and extracellular conductivities, and the shape and extent of the source function (either the transmembrane potential or the intracellular potential) on the solutions are discussed. The results show that, in general, the approximate solutions are unsatisfactory for computing the surface extracellular potential when the single fiber is used to represent a large bundle (greater than 300 microns).

Full Text

Duke Authors

Cited Authors

  • Trayanova, NA; Henriquez, CS; Plonsey, R

Published Date

  • January 1990

Published In

Volume / Issue

  • 37 / 1

Start / End Page

  • 22 - 35

PubMed ID

  • 2154399

Pubmed Central ID

  • 2154399

Electronic International Standard Serial Number (EISSN)

  • 1558-2531

International Standard Serial Number (ISSN)

  • 0018-9294

Digital Object Identifier (DOI)

  • 10.1109/10.43608


  • eng