[Motor evoked potentials. Physiology, indications, safety aspects].

The motor cortex and the proximal part of the peripheral nervous system can be stimulated by a rapidly changing magnetic field. The procedure is simple, painless and safe. It allows to quantify the function of the most rapidly conducting corticospinal fibers. It is possible to detect subclinical lesions. The use of this technique for the study of lesions of the proximal parts of the peripheral nervous system is as of yet largely experimental.