The pathophysiological concept of migraine presently held attributes the major changes to vascular factors. Therefore, it seemed appropriate to use rheoencephalography to test cerebral hemodynamics in cases of migraine. This very harmless and well suited method revealed: (1) on routine tracings during the painless intervall only 1/7 of the cases showed significant changes, while more than 2/3 could be classified with the help of an orthostatic stress test under REG-observation; (2) REG is more often correct for diagnosis than EEG and this does not surprise since REG monitors cerebral hemodynamics directly while EEG records activity for parenchyma and thus only secondarily depends on circulation; (3) similar conditions were previously seen in Meniere's disease where EEG also is less efficient than REG. According to the results of this study, it should be interesting to include REG in the work-up of migrainous patients. In these and under similar conditions, REG will be of diagnostic value.