Extended dynamical range as a collective property of excitable cells

Abstract

Receptor cells with electrically coupled axons can improve both their input sensitivity and dynamical range due to collective non-linear wave properties. This mechanism is illustrated by a network of axons modeled by excitable maps subjected to a Poison signal process with rate r. We find that, in a network of N cells, the amplification factor A (number of cells excited by a single signal event) decreases smoothly from A= O(N) to A=1 as r increases, preventing saturation in a self-organized way and leading to a Weber-Fechner law behavior. This self-limited amplification mechanism is generic for excitable media and could be implemented in other biological contexts and artificial sensor devices.