Basic mechanisms of magnetic coil excitation of nervous system in humans and monkeys and their applications

Conclusions from studies utilizing the human peripheral nerve as a model system in developing the optimal magnetic coil (MC) orientation for focal stimulation were applied to the human cerebral cortex. The theoretical predictions were validated by direct recording from corticospinal neurons in the monkey. Appropriate MC orientation over the cerebral cortex elicits: (1) minimal central motor delays; (2) movements of individual digits; (3) a sense of movement in a paralyzed arm; (4) laryngeal muscle excitation from frontal areas related to speech; (5) suppression of visual perception when the MC is over the visual cortex; and (6) transcallosal responses in the opposite hemisphere.<
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