Research Library
Written by the Relief Team · Pathophysiology

Cortical Spreading Depression: The Physiological Substrate of Aura

At the core of the migraine event is Cortical Spreading Depression (CSD) — a slow-moving wave of depolarization that migrates across the cerebral cortex, followed by a prolonged period of inhibition. This wave is what patients perceive as aura.

The Role of CGRP

When this electrical wave reaches pain receptors in the meninges, it triggers CGRP (Calcitonin Gene-Related Peptide) release. CGRP causes blood vessels to swell and sensitizes pain fibers, resulting in that characteristic throbbing pulse.

The Habituation Deficit

A healthy brain filters out repetitive environmental data. A migrainous brain, however, lacks sensory habituation. It remains in a state of high alert, processing every light, sound, and smell at maximum intensity — leading to central sensitization over time.

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