Reduced gating of middle-latency auditory evoked potentials (P50) in migraine patients: another indication of abnormal sensory processing?

Habituation of cortical evoked responses to repetitive stimuli is reduced i n migraine between attacks. To explore another aspect of information proces sing, we measured auditory sensory gating. The amplitude of the P50 respons e to the second of two homologous stimuli was significantly less reduced in migraineurs than in healthy volunteers. This lack of auditory sensory gati ng may be due to a hypofunction of monoaminergic subcortico-cortical pathwa ys, which is also supposed to cause the interictal deficit of cortical habi tuation to repetitive stimuli. (C) 2001 Elsevier Science Ireland Ltd. All r ights reserved.