  Objective: We propose a novel approach for modelling the inter-dependence of
electrical and mechanical phenomena in nervous cells, by using electro-thermal
equivalences in finite element (FE) analysis so that existing thermo-mechanical
tools can be applied. Methods: First, the equivalence between electrical and
thermal properties of the nerve materials is established, and results of a pure
heat conduction analysis performed in Abaqus CAE Software 6.13-3 are validated
with analytical solutions for a range of steady and transient conditions. This
validation includes the definition of equivalent active membrane properties
that enable prediction of the action potential. Then, as a step towards fully
coupled models, electromechanical coupling is implemented through the
definition of equivalent piezoelectric properties of the nerve membrane using
the thermal expansion coefficient, enabling prediction of the mechanical
response of the nerve to the action potential. Results: Results of the coupled
electro-mechanical model are validated with previously published experimental
results of deformation for the squid giant axon, crab nerve fibre and garfish
olfactory nerve fibre. Conclusion: A simplified coupled electro-mechanical
modelling approach is established through an electro-thermal equivalent FE
model of a nervous cell for biomedical applications. Significance: One of the
key findings is the mechanical characterization of the neural activity in a
coupled electro-mechanical domain, which provides insights into the
electromechanical behaviour of nervous cells, such as thinning of the membrane.
This is a first step towards modelling 3D electromechanical alteration induced
by trauma at nerve bundle, tissue and organ levels.
