A Phase-by-Phase Review of Migraine Pathophysiology.

Migraine is a common, disabling neurological disorder characterized by multiple phases: premonitory, aura, headache, postdrome, and interictal. Our understanding of the pathophysiology of each phase of migraine has evolved over recent years. The premonitory phase begins as early as 3 days before the headache phase, and involves a complex interplay between various cortical and subcortical brain regions, including the hypothalamus and brainstem nuclei that modulate nociceptive signaling. The headache phase involves activation of the trigeminovascular system, a pathway that is well characterized. In one-third of patients, an aura phase may occur during some attacks and likely correlates with a cortical spreading depression-like event; a slowly propagating wave of neuronal and glial cell depolarization and hyperpolarization. Improved characterization of the pathophysiological processes involved at each stage of the migraine attack will aid the identification of new therapeutic targets for migraine prevention. This review provides an update on prevailing concepts of migraine pathophysiology.