Dimensions of pain catastrophising and specific structural and functional alterations in patients with chronic pain: Evidence in medication-overuse headache.

We examined the neuroanatomical substrate of different pain catastrophising (PC) dimensions (i.e. rumination; magnification; helplessness) in patients with medication-overuse headache (MOH). We included 18 MOH patients who were administered the Pain Catastrophizing Scale (PCS) and scanned in a 3T-MRI. We conducted whole-brain volumetric and resting-state functional connectivity (FC) analysis to examine the association between grey matter (GM) density and FC strength and PCS dimensions controlling for depression and anxiety. Higher total PCS score was associated with decreased GM density in precentral and inferior temporal gyrus, increased FC between middle temporal gyrus and cerebellum and reduced FC between precuneus and inferior temporal gyrus, as well as between frontal pole and temporal fusiform cortex. Regarding PCS dimensions, we mainly observed the involvement of (1) somatosensory cortex, supramarginal gyrus, basal ganglia, core default-mode network (DMN) in rumination; (2) somatosensory cortex, core DMN, dorsal medial prefrontal cortex (DMPFC)-DMN subsystem and cerebellum in magnification; and (3) temporal regions, DMN and basal ganglia in helplessness. PC dimensions are associated with a specific structural and functional neuroanatomical pattern, which is different from the pattern observed when PC is considered as a single score. The involvement of basal ganglia and cerebellum needs further investigation.