Roth B J, Basser P J
Division of Research Services, National Institutes of Health, Bethesda, MD 20892.
IEEE Trans Biomed Eng. 1990 Jun;37(6):588-97. doi: 10.1109/10.55662.
A model is presented to explain the physics of nerve stimulation by electromagnetic induction. Maxwell's equations predict the induced electric field distribution that is produced when a capacitor is discharged through a stimulating coil. A nonlinear Hodgkin-Huxley cable model describes the response of the nerve fiber to this induced electric field. Once the coil's position, orientation, and shape are given and the resistance, capacitance, and initial voltage of the stimulating circuit are specified, this model predicts the resulting transmembrane potential of the fiber as a function of distance and time. It is shown that the nerve fiber is stimulated by the gradient of the component of the induced electric field that is parallel to the fiber, which hyperpolarizes or depolarizes the membrane and may stimulate an action potential. Finally, it predicts complicated dynamics such as action potential annihilation and dispersion.
提出了一个模型来解释通过电磁感应进行神经刺激的物理原理。麦克斯韦方程组预测了电容器通过刺激线圈放电时产生的感应电场分布。一个非线性霍奇金 - 赫胥黎电缆模型描述了神经纤维对该感应电场的响应。一旦给出线圈的位置、方向和形状，并指定刺激电路的电阻、电容和初始电压，该模型就可以预测纤维产生的跨膜电位随距离和时间的变化。结果表明，神经纤维受到与纤维平行的感应电场分量的梯度刺激，该梯度使膜超极化或去极化，并可能刺激动作电位。最后，它预测了诸如动作电位湮灭和离散等复杂动力学。
