The anatomic and physiologic bases of motor-evoked potentials.

The anatomophysiologic mechanisms underlying noninvasive stimulation of brain, spinal cord, and roots via electric and magnetic impulses are surveyed. Different types of technical approaches as well as the methods for measurements of the conduction times of central motor tracts are fully described. Safety aspects are also reviewed. This new neurophysiologic technique, since its recent introduction, has explosively expanded both in its research and clinical applications.