The electrophysiology of migraine

Migraine is currently regarded as a neurovascular disorder of trigeminal sensory processing, generated centrally, probably at the level of the brainstem. In the past, electrophysiological techniques have drawn no definite conclusions on either interictal or ictal changes in migraineurs compared with controls, largely because of methodological differences. Recently, two findings have been shown consistently: an interictal increasing lack of habituation of evoked potentials with a normalization at the start of the attack and strong intensity dependence of auditory evoked potentials. These findings substantiate migraine sufferers as having an abnormal trait interictally, with the attack characterized by a change in the state of central processing. Exploitation of these differences may be a useful tool to study the mechanism of action of drugs used for the treatment of migraine.