Fourteen CSM patients with clinical findings of myelopathy had their diagnoses proved with MRI imaging and at operation. There were a control group of 28 normal subjects for MEP and another control group of 32 for SEP. The results of the study showed that 72.7% had MEP abnormality with prolongation of the central motor conduction time (CMCT) in 7 cases and absence of motor action potentials after C7 stimulation in one of the 11 patients. In 2 patients with prolongation of CMCT, normal SEPs were found in the same arm while 1 patient showed directly a reversal of the results. The short-term follow-up study in 10 patients showed normalization of the prolonged CMCT in one and reappearance of motor action potentials with C7 stimulation in another. The authors considered that the non-invasive and painless, transcranial magnetic stimulation of the motor pathways might be useful in the assessment and management of CSM patients and better than the electrical stimulation.