Thalamo-cortical network activity during spontaneous migraine attacks

Objective: We used MRI to search for changes in thalamo-cortical networks and thalamic microstructure during spontaneous migraine attacks by studying at the same time structure with diffusion tensor imaging and resting state function in interconnected brain networks with independent component analysis. Methods: Thirteen patients with untreated migraine without aura (MI) underwent 3T MRI scans during an attack and were compared to a group of 19 healthy controls (HC). We collected resting state data in 2 selected networks identified using group independent component (IC) analysis. Fractional anisotropy (FA) values of bilateral thalami were calculated in the same participants and correlated with resting state IC z scores. Results: Functional connectivity between the executive and the dorso-ventral attention networks was reduced in MI compared to HC. In HC, but not in MI, the higher the IC24 z score, encompassing interconnected areas of the dorso-ventral attention system, the lower the bilateral thalamic FA values. In patients, the higher the executive control network z scores, the lower the number of monthly migraine days. Conclusions: These results provide evidence for abnormal connectivity between the thalamus and attentional cerebral networks at rest during migraine attacks. This abnormality could subtend the known ictal impairment of cognitive performance and suggests that the latter might worsen with increasing attack frequency.