Neuron physiology is actually described using the well known models created by Hodgkin-Huxley (HH) and their derivatives which came later, the Fitzhugh-Nagumo (FN) equations. These attempts to understand the internal functioning of the neuron are unfortunately far from the strict Nature's observation. These equations, particularly, are unable to explain an unidirectional propagation of action p...

Neuron physiology is actually described using the well known models created by Hodgkin-Huxley (HH) and their derivatives which came later, the Fitzhugh-Nagumo (FN) equations. These attempts to understand the internal functioning of the neuron are unfortunately far from the strict Nature's observation. These equations, particularly, are unable to explain an unidirectional propagation of action p...

The invasion of fast (Na+) spikes from the soma into dendrites was studied in single pyramidal cells of the sensorimotor cortex by simultaneous extracellular recordings of the somatic and dendritic action potentials in freely behaving rats. Field potentials and unit activity were monitored with multiple-site silicon probes along trajectories perpendicular to the cortical layers at spatial inter...

It has become of fundamental importance to understand variations in the shape of the upstroke of the action potential in order to identify structural loading effects. One component of this goal is a detailed experimental analysis of the time course of the foot of the cardiac action potential (Vm foot) during propagation in different directions in anisotropic cardiac muscle. To this end, we perf...

When the propagation velocity of action potentials is modified by changing the internal resistance of a cell, cable theory predicts that the shape of the action potential upstroke should not change; changes in velocity associated with changes in the upstroke usually are attributed to changes in membrane properties. However, we observed, in normal cardiac muscle, that changes in the upstroke wit...

This paper presents a method to mathematically analyze the nerve impulse propagation in nonuniform axons. Starting from the general, nonlinear one-dimensional cable equations with spatially varying cable diameter, the problem is shown to be eqiuvalent (under some variable transformations) to the case of uniform axons. Characterized by the same normal form, six functions for analytically treatab...

Lamotrigine (LTG) is an anti-epileptic drug that is widely used clinically in various neuropsychiatric disorders. Although consensus is found on the general mode of action by LTG on voltage-gated sodium current, its effect on field potential, neuropropagation, and long-term potentiation, especially in prefrontal cortex (PFC), is still not understood completely. We investigated LTG effects on sy...

Nerve conduction in unmyelinated fibers has long been described based on the equivalent circuit model and cable theory. However, without the change in ionic concentration gradient across the membrane, there would be no generation or propagation of the action potential. Based on this concept, we employ a new conductive model focusing on the distribution of voltage-gated sodium ion channels and C...

When the propagation velocity of action potentials is modified by changing the internal resistance of a cell, cable theory predicts that the shape of the action potential upstroke should not change; changes in velocity associated with changes in the upstroke usually are attributed to changes in membrane properties. However, we observed, in normal cardiac muscle, that changes in the upstroke wit...

It is known, from both experiments and simulations, that cardiac action potentials are shortened near a non-conducting boundary. In the present paper, this effect is studied in a simple, two-current ionic model, with propagation restricted to a 1D fibre. An asymptotic approximation for the dependence of action potential duration on distance to the boundary is derived. This estimate agrees well ...