P9 in median nerve SEPs is a junctional potential generated by the change of the volume conductor size between trunk and neck

A Mochizuki; M Sonoo; T Shimizu; M Iwata

doi:10.1016/s0168-5597(98)00039-2

P9 in median nerve SEPs is a junctional potential generated by the change of the volume conductor size between trunk and neck

Electroencephalogr Clin Neurophysiol. 1998 Nov;108(6):584-7. doi: 10.1016/s0168-5597(98)00039-2.

Authors

A Mochizuki¹, M Sonoo, T Shimizu, M Iwata

Affiliation

¹ Department of Neurology, Teikyo University School of Medicine, Tokyo, Japan.

PMID: 9872430
DOI: 10.1016/s0168-5597(98)00039-2

Abstract

Objectives: We aimed to investigate the origin of P9 in median SEPs by applying the junctional potential theory.

Methods: We studied the distribution over the body surface with contralateral shoulder reference in 4 normal subjects.

Results: A stationary potential field P9/tN9 (=truncal N9) was recorded: P9 over head and neck (the smaller part), tN9 over trunk (the larger part), the boundary being located between trunk and neck. This polarity agreed with that expected from simulation studies.

Conclusions: P9 is a junctional potential generated by the change of the volume conductor size between trunk and neck.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Body Surface Potential Mapping
Evoked Potentials, Somatosensory / physiology*
Humans
Median Nerve / physiology*
Neural Conduction / physiology*