Migraine, cortical excitability and evoked potentials: a clinico-pharmacological perspective

Coppola et al ., (2005) studied somatosensory evoked high-frequency oscillations (HFO) in migraine patients between attacks and advances the hypothesis that the habituation deficit in migraine patients is owing to a reduced pre-activation level of sensory cortices. While further proposing that a reduced interictal excitation (‘pre-activation’) level might be the pathophysiological basis of migraine attacks, these authors acknowledge that contradictory laboratory evidence for both increased and decreased cortical excitability as well as decreased and normal function of inhibitory cortical interneurons have been presented by other investigators through study of transcranial magnetic stimulation and psychophysical studies. Additionally, the paucity of definitive knowledge about neural generators involved in HFOs is underscored.It is essential to maintain a clear conceptual distinction regarding the state of the brain physiology between the headache and the headache-free states in migraine. Hypersensitivity to light or noise is a migraine attack-related phenomenon; nevertheless, such hypersensitivity cannot be used to support the concept of cerebral cortex hyperexcitability between attacks. Second, a critical limitation of this study (Coppola et al ., 2005) is the decision to select a …