Modeling the effects of electric fields on nerve fibers: Determination of excitation thresholds

A method for predicting excitation of axons based on the response of passive models is proposed. An expression describing the transmembrane potential induced in passive models to an applied electric field is presented. Two terms drive the polarization of each node: a source term described by the activating function at the node, and an ohmic term resulting from redistribution of current from sources at other nodes. It is shown that a total equivalent driving function including both terms can be used to provide predictions of excitation thresholds for any applied field. The method requires only knowledge of the intracellular strength-duration relationship of the axon, the passive step response of the axon to an intracellular current, and the values of the extracellular potentials. Excitation thresholds for any given applied field can then be calculated using a simple algebraic expression. This method eliminates the errors associated with use of the activating function alone, and greatly reduces the computation required.<<ETX>>

[1]  J.H. Meier,et al.  Simulation of multipolar fiber selective neural stimulation using intrafascicular electrodes , 1992, IEEE Transactions on Biomedical Engineering.

[2]  Warren M. Grill,et al.  A New Formulation Of The Activating Function For Estimation Of Neural Excitation Thresholds , 1991, Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society Volume 13: 1991.

[3]  J. T. Mortimer,et al.  A Numerical Analysis Of The Electric Field Generated By A Nerve Cuff Electrode , 1991, Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society Volume 13: 1991.

[4]  D. A. Ksienski,et al.  A nerve cuff technique for selective excitation of peripheral nerve trunk regions , 1990, IEEE Transactions on Biomedical Engineering.

[5]  Frank Rattay,et al.  Electrical Nerve Stimulation , 1990 .

[6]  Dominique M. Durand,et al.  Optimization of coil design for neuronal excitation by magnetic stimulation , 1989, Images of the Twenty-First Century. Proceedings of the Annual International Engineering in Medicine and Biology Society,.

[7]  F. Rattay Analysis of models for extracellular fiber stimulation , 1989, IEEE Transactions on Biomedical Engineering.

[8]  F. Rattay,et al.  Modeling the excitation of fibers under surface electrodes , 1988, IEEE Transactions on Biomedical Engineering.

[9]  D. Durand,et al.  FINITE DIFFERENCE MODELING OF NERVE CUFF ELECTRIC FIELDS. , 1987 .

[10]  Dominique M. Durand,et al.  MODELING OF MAMMALIAN MYELINATED NERVE FOR FUNCTIONAL NEUROMUSCULAR STIMULATION. , 1987 .

[11]  C. Nicholson,et al.  A model for the polarization of neurons by extrinsically applied electric fields. , 1986, Biophysical journal.

[12]  F. Rattay Analysis of Models for External Stimulation of Axons , 1986, IEEE Transactions on Biomedical Engineering.

[13]  D. Stegeman,et al.  Solution Methods of Electrical Field Problems in Physiology , 1982, IEEE Transactions on Biomedical Engineering.

[14]  Donald R. McNeal,et al.  Comparison of a Dynamic and Steady-State Model for Determining Nerve Fiber Threshold , 1978, IEEE Transactions on Biomedical Engineering.

[15]  D. Mcneal Analysis of a Model for Excitation of Myelinated Nerve , 1976, IEEE Transactions on Biomedical Engineering.

[16]  D. B. Heppner,et al.  Considerations of quasi-stationarity in electrophysiological systems. , 1967, The Bulletin of mathematical biophysics.

[17]  A. Huxley,et al.  The action potential in the myelinated nerve fibre of Xenopus laevis as computed on the basis of voltage clamp data , 1964, The Journal of physiology.

[18]  A. Hodgkin,et al.  A quantitative description of membrane current and its application to conduction and excitation in nerve , 1952, The Journal of physiology.