ABSTRACT
This chapter reviews the main biophysical and mathematical methods used to model electrical field effects. A hypothetical mechanism of ephaptic interactions in the hippocampus was described. First, the cerebral cortex is one of the major loci of epileptiform discharges, and ephaptic interaction has been demonstrated to be an important factor in epileptiform discharging in the hippocampus. Stimulated excitable cells generate electrical fields which can have detectable effects on neighboring cells: this effect is known as electrical field effect, electrical interaction, electrical field interaction, or electrical field coupling between neurons. The model can be simplified if consider one-dimensional neurons in a three-dimensional extracellular space. When the stimulation effect is below the action potential threshold, one can observe an excitatory post-synaptic potential at the stimulated neuron, together with a non-monotonic variation of the unstimulated neuron depolarization; these results can be compared to those obtained using an analytical method.
