Integrated anatomical and functional connectivity mapping in episodic migraine: a spectral graph theory approach.

Migraine disproportionately affects women, yet how migraine physiology reshapes large-scale brain communication remains unclear. We combined diffusion-weighted imaging (DWI) and resting-state fMRI in female participants (14 patients with episodic migraine without aura; 15 matched healthy controls) to test how direct and indirect anatomical communication paths in the brain can predict brain function. We used a spectral mapping framework that isolates the contribution of communication paths of a specific length and evaluated how well brain structure predicts brain function within individuals. Analyses of individual path lengths revealed a non-monotonic dissociation: no difference at one-step (direct) paths, but higher mapping accuracy in patients at intermediate indirect scales (four and five steps). At longer scales, contributions attenuated in both groups. Spatial correspondence analyses localized patient-specific effects to default mode network subsystems across multiple atlases. These findings indicate that migraine-related dysfunction reflects altered mesoscale structure-function integration along indirect anatomical routes, and they provide a general approach to dissect structure-function coupling by communication scale in disease.