In six patients suffering from a multifocal neurological disease of the demyelinating type, a somatosensory evoked response was analyzed in the cortical and cervical area after stimulating the right index finger and the right nervus suralis. The results of the investigation with this method indicate that localization of the central nervous system pathology seems to lie within the realms of possibility, in which case this method will be a useful addition to the tools used to evaluate quantitatively the results of different treatments in this type of disease.