  We present a novel mathematical approach to model noise in dynamical systems.
We do so by considering dynamics of a chain of diffusively coupled Nagumo cells
affected by noise. We show that the noise in transmembrane current can be
effectively modelled as fluctuations in electric characteristics of the
membrane. The proposed approach to model noise in a nerve fibre is different
from the standard additive stochastic current perturbation (the Langevin type
equations).
