New plasmon-polariton model of the saltatory conduction

Abstract

We propose a new model of the saltatory conduction in myelinated axons. This conduction of the action potential in myelinated axons does not agree with the conventional cable theory, though the latter has satisfactorily explained the electrosignaling in dendrites and in unmyelinated axons. By the development of the wave-type concept of ionic plasmon-polariton kinetics in axon cytosol we have achieved an agreement of the model with observed properties of the saltatory conduction. Some resulting consequences of the different electricity model in the white and the gray matter for nervous system organization have been also outlined. SIGNIFICANCEMost of axons in peripheral nervous system and in white matter of brain and spinal cord are myelinated with the action potential kinetics speed two orders greater than in dendrites and in unmyelinated axons. A decrease of the saltatory conduction velocity by only 10% ceases body functioning. Conventional cable theory, useful for dendrites and unmyelinated axon, does not explain the saltatory conduction (discrepancy between the speed assessed and the observed one is of one order of the magnitude). We propose a new nonlocal collective mechanism of ion density oscillations synchronized in the chain of myelinated segments of plasmon-polariton type, which is consistent with observations. This model explains the role of the myelin in other way than was previously thought.