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We used voxel-based morphometry (VBM) to compare grey matter volume (GMV) between 20 migraine patients (five with aura and 15 without aura) with normal conventional magnetic resonance imaging findings and 33 healthy controls matched for age and sex. A separate analysis was also performed to delineate a possible correlation between the GMV changes and the headache duration or lifetime headache frequency. When compared with controls, migraine patients had significant GMV reductions in the bilateral insula, motor/premotor, prefrontal, cingulate cortex, right posterior parietal cortex, and orbitofrontal cortex (P < 0.001, uncorrected for multiple comparisons at a voxel level; corrected P < 0.05 after small volume corrections). All regions of the GMV changes were negatively correlated with headache duration and lifetime headache frequency (P < 0.05, Pearson's correlation test). We found evidence for structural grey matter changes in patients with migraine. Our findings of progressive GMV reductions in relation to increasing headache duration and increasing headache frequency suggest that repeated migraine attacks over time result in selective damage to several brain regions involved in central pain processing.