Dynamic Moment Analysis of the Extracellular Electric Field of a Biologically Realistic Spiking Neuron

TL;DR

This paper introduces a moment expansion method to efficiently analyze the extracellular electric field generated by a realistic neuron model, revealing significant quadrupole contributions affecting fields up to 1 cm.

Contribution

It presents a novel, rapid computational approach using moment expansion to analyze extracellular fields from biologically realistic neuron models.

Findings

Quadrupole moments significantly influence extracellular fields.

The method efficiently computes fields near and far from neurons.

Extracellular fields can extend up to nearly 1 cm from the neuron.

Abstract

Based upon the membrane currents generated by an action potential in a biologically realistic model of a pyramidal, hippocampal cell within rat CA1, we perform a moment expansion of the extracellular field potential. We decompose the potential into both inverse and classical moments and show that this method is a rapid and efficient way to calculate the extracellular field both near and far from the cell body. The action potential gives rise to a large quadrupole moment that contributes to the extracellular field up to distances of almost 1 cm. This method will serve as a starting point in connecting the microscopic generation of electric fields at the level of neurons to macroscopic observables such as the local field potential.