Mechanical Changes in Crab Nerve Fibers during Action Potentials

Abstract

A nerve impulse travelling along a crustacean nerve was found to be accompanied by a small, rapid movement of the nerve surface.The movement was 10-20nm in amplitude and was concurrent with a rise in the “swelling pressure” of the order of 5mg/cm² for a nerve bundle.Initiation of an action potential at the site of cathodal polarization was preceded by a small, slow mechanical change in the nerve fiber.Anodal polarization produced a large mechanical change of the opposite sign.Tetrodotoxin and procaine suppressed rapid mechanical changes.