Intensity dependence of auditory evoked cortical potentials in migraine. Changes in the peri-ictal period.

The presence of premonitory symptoms in about 20% of patients suggest that the migraine attack is initiated long before the occurrence of the aura or headache symptoms. Recording of evoked and event-related potentials has revealed a strong intensity dependence of auditory evoked potentials (IDAP) in migraine with and without aura. We studied changes in IDAP in the peri-ictal period in 63 migraine patients (55 presenting migraine without aura, four migraine with aura, and four both types) and compared findings with interictal controls. The results of this study indicated that cortical processing of sensory information tends to normalize just before and during an attack. The normalization of IDAP may reflect an increase in central serotonergic activity. The study has been published in Cephalalgia (Afra J, Sándor PS, Schoenen J. Cephalalgia 2000;20:714-719).