[Cerebral refractory period of the somatosensory system in diseases of the central nervous system (author's transl)].

The duration of the refractory period of the somatosensory system was determined through the lengthening of latency respectively through the loss of Minimum 1 and Maximum 1; the median nerve was stimulated by single and double stimuli of variable interval, the somatosensory evoked potentials (SRAP) were averaged contralateral. The relative refractory time is independent of age, the absolute refractory time increased with advanced age. In genuine epilepsy with 3/s spike-waves the relative refractory period is shortened compared with the reference group of normal subjects. In multiple sclerosis the relative refractory time is distinctly increases in sign of demyelination on conduction in the central nervous system. The most distinct delays of refractory period are in cases with cerebrovascular disease and brain atrophy. The correlation between the clinical and neurophysiological results shows, that the single and double stimulation of the median nerve, combined with the analysis of the evoked potentials and the cerebral refractory period, is a good neurophysiologic cerebral function-test.