A model of the muscle-fiber intracellular action potential waveform, including the slow repolarization phase

Author

McGill, Kevin C. ; Lateva, Zoia C.

Author_Institution

VA Palo Alto Health Care Syst., Rehabilitation Res. & Dev. Center, Palo Alto, CA, USA

Volume

48

Issue

12

fYear

2001

fDate

12/1/2001 12:00:00 AM

Firstpage

1480

Lastpage

1483

Abstract

Recent studies have shown that the slow repolarization phase or "negative afterpotential" of the intracellular muscle-fiber action potential (IAP) plays an important role in determining the shape of the extracellularly recorded motor-unit action potential (MUAP). This paper presents a model of the IAP waveform as the sum of a spike and an afterpotential, both represented by simple analytical expressions. The model parameters that specify the sizes of the spike and afterpotential are shown to be proportional to the quadrupole and dipole moments of the transmembrane current distribution associated with the spike of the wave of excitation. The model provides a computationally efficient method for simulating the MUAP, and it can be reliably inverted to estimate the model parameters from empirical IAP and MUAP waveforms

Keywords

cellular biophysics; electromyography; fibres; parameter estimation; physiological models; EMG; afterpotential; dipole moments; excitation wave spike; muscle-fiber intracellular action potential waveform model; quadrupole moments; simple analytical expressions; slow repolarization; slow repolarization phase; spike; transmembrane current distribution; Anatomy; Biomembranes; Conductors; Convolution; Current distribution; Difference equations; Extracellular; Muscles; Optical fiber theory; Shape;

fLanguage

English

Journal_Title

Biomedical Engineering, IEEE Transactions on

Publisher

ieee

ISSN

0018-9294

Type

jour

DOI

10.1109/10.966607

Filename

966607