Abstract

A first energy field is applied to a neural cell to be stimulated from a polarized quiescent state to an active depolarized state. The first field changes the cell from the quiescent state so the cell transmembrane potential differs from both of the states. While the transmembrane potential differs from both the states a field including a cyclic magnetic component is applied to the cell. The cyclic magnetic component has a frequency and amplitude and is combined with effects from the first energy field such that each cycle of the cyclic magnetic component causes an incremental change in transmembrane potential of the cell without changing the cell from the quiescent to the active state. The cyclic magnetic component applied to the cell has a duration and amplitude and is combined with the effects of the first energy field to cause an accumulation of the incremental changes to change the cell state from the quiescent to the active state.

Other References

• Reilly, "Electrical Models for Neural Excitation Studies," Johns Hopkins APL Technical Digest, vol. 9, No. 1 1988, pp. 44-59
• Reilly,Electrical Stimulation and Electropathology, 1992, chapter 4, "Excitation Models"
• Amassian et al., "Focal stimulation of human cerebral cortex with the magnetic coil: a comparison with electrical stimulation," Electroencephalography and clinical Neurophysiology, 1989, pp. 401-416
• Mills et al., "Magnetic brain stimulation with a double coil: the importance of coil orientation," Electroencephalography and clinical Neurophysiology, 85, 1992, pp. 17-21
• Cohen et al., "Effects of coil design on delivery of focal magnetic stimulation. Technical considerations," Electroencephalography and clinical Neurophysiology, 1990, 75, pp. 350-357
• S. Chokroverty et al., Magnetic Stimulation in Clinical Neurophysiology, 1990
• H. Eaton, "Electric field induced in a spherical volume conductor from arbitrary coils: application to magnetic stimulation and MEG," Medical & Biological Engineering & Computing, Jul. 1992, pp. 433-440
• H. Eaton, "Magnetic Nerve Stimulation," Johns Hopkins AFL Technical Digest, vol. 12, No. 2, 1991, pp. 153-158
• D. Cohen et al., "Developing a More Focal Magnetic Stimulator, Part I: Some Basic Principles," Journal of Clinical Neurophysiology, vol. 8, No. 1, 1991, pp. 102-111
• K. Yunokuchi et al., "Developing a More Focal Magnetic Stimulator. Part II: Fabricating Coils and Measuring Induced Current Distributions," Journal of Clinical Neurophysiology, vol. 8, No. 1, 1991, pp. 112-120
• J. Cadwell, The Design and Applications of Cadwell Magnetic Coil