Magnetic peripheral nerve stimulation: axial versus transverse fields

In-situ magnetic nerve stimulation experiments have provoked the hypothesis that nerve fibers can be activated with transverse fields. Objections are that tissue inhomogeneities and fiber undulations gave the necessary axial field components, making the hypothesis superfluous. We confirm the experimental results in in-vitro experiments, where the influence of inhomogeneities was minimized. Stretching the nerve, to reduce fiber-undulations, increased the stimulus threshold for both coil positions