[Migraine: a disorder of sensory stimulus modulation? Empirical studies based on contingent negative variation.].

Several studies of contingent negative variation (CNV) examined whether this method provides a suitable basis for research on pathogenetic processes in chronic headaches-especially migraine. In the present study, the CNV amplitudes and CNV course of 23 migraine patients were compared with those of 22 healthy subjects. CNV was calculated for (a) "total interval", (b) "early CNV component", and (c) "late CNV component". In 32 trials with an interstimulus interval of 3 s results showed a significant higher CNV in the migraine group. While the amplitude of healthy subjects diminished quickly, the amplitudes of migraine patients remained stable during the session. The results allow the assumption that the higher level of CNV amplitude in migraine patients is not only due to higher cortical noradrenergic or serotoninergic activation. This study shows that migraine patients cannot decrease their CNV amplutides. This is probably due to defective processing of sensory imput.