Flow driven control of pulse width in excitable media

TL;DR

This paper investigates how fluid flow influences pulse width in excitable media, revealing that advective coupling allows for linear control of pulse width without affecting pulse velocity, through theoretical analysis of the Fitzhugh-Nagumo model.

Contribution

It introduces a novel theoretical framework incorporating advective coupling in the Fitzhugh-Nagumo model to control pulse width independently of pulse velocity.

Findings

Advective coupling enables linear control of pulse width.

Pulse velocity remains unaffected by flow coupling.

Flow can be used to modulate pulse characteristics independently.

Abstract

Models of pulse formation in nerve conduction have provided manifold insight not only into neuronal dynamics but also the non-linear dynamics of pulse formation in general. Recent observation of neuronal electro-chemical pulses also driving mechanical deformation of the tubular neuronal wall and thereby generating ensuing cytoplasmic flow now question the impact of flow on the electro-chemical dynamics of pulse formation. We, here, theoretically investigate the classical Fitzhugh-Nagumo model now accounting for advective coupling between the pulse propagator typically describing membrane potential and here triggering mechanical deformations and, thus, governing flow magnitude, and the pulse controller, a chemical species advected with the ensuing fluid flow. Employing analytical calculations and numerical simulations we find, that advective coupling allows for a linear control of pulse width while leaving pulse velocity unchanged. We therefore uncover an independent control of pulse width by fluid flow coupling.