Electrophysiological response patterns ofprimary sensory cortices in migraine

Migraine is an ictal disorder characterised by a particular vulnerability of patients to sensoryoverload, both during and outsideof the attack. Central nervous system dysfunctions are supposed toplay a pivotal role in migraine. Electroneurophysiological methods, which aim to investigate sensory processing, seem thus particularly appropriate to study the pathophysiology of migraine. We have thus reviewed evoked potential studies performed in migraine patients. Although results are in part contradictory, these studies nonetheless demonstrate an interictal dysfunction of sensory cortices,and possibly of subcortical structures, in migraine with and without aura. The predominant abnormalityis a deficient habituation of evoked responses to repeated stimuli, probably due to cortical, and possibly widespread neural, "dysexcitability".