Interictal Resting-State Connectivity of the Insula Is Altered in Migraine Without Aura (S32.006)

OBJECTIVE: To explore the intrinsic connectivity of selected networks in episodic migraineurs without aura compared to healthy controls. BACKGROUND: Migraine attacks are characterized by head pain and sensitivity to sensory stimuli. This sensory sensitivity may persist, to a lesser degree, between attacks as migraineurs have lower interictal thresholds for light-, sound-, and pressure-induced discomfort than controls. Task-free functional magnetic resonance imaging (fMRI) identifies brain regions that exhibit correlated low-frequency blood oxygen level-dependent (BOLD) signal patterns, termed intrinsic connectivity networks (ICNs). Previously identified ICNs include the visual and auditory networks, as well as a “salience network,” whose function may be to determine the relative significance of internal and external stimuli amongst a myriad of inputs. Based on the clinical phenotype of pain and sensory sensitivity, we sought to explore the interictal intrinsic connectivity of sensory networks, the salience network, and the dorsal pons, which is known to be active during migraine attacks, in patients with episodic migraine without aura. METHODS: Using task-free fMRI and a region-of-interest analysis, we compared four intrinsic connectivity networks in fifteen migraineurs without aura versus fifteen age- and gender-matched healthy controls by placing seeds in the calcarine cortex, Heschl’s gyrus, the dorsal pons, and the right anterior insula. We also examined the relationship between network connectivity, migraine frequency, and sensory sensitivity. RESULTS: Migraineurs showed increased connectivity between the visual and auditory networks and the right dorsal anterior insula, between the dorsal pons and the right dorsal mid-insula, and between the right and left ventral anterior insulae. Increased connectivity showed no correlation with migraine frequency or sensory sensitivity. CONCLUSIONS: Patients with migraine display interictal changes in the topology of intrinsic connections, with greater connectivity between sensory networks, the pons, and the insula, a region that represents nociceptive and autonomic information and has multiple functions ranging from interoception to exteroceptive attention. Disclosure: Dr. Tso has nothing to disclose. Dr. Trujillo has nothing to disclose. Dr. Guo has nothing to disclose. Dr. Goadsby has received personal compensation for activities with Allergan, Inc., Colucid, MAP Pharmaceuticals, Merck Sharp & Dohme Limited, eNeura, ATI, Boston Scientific Corporation, Eli Lilly & Company, Medtronic, Inc., Bristol-Myers Squibb Company, Amgen Inc., Arteaus, AlderBio, Pfizer Inc., Zogeniz, Nevrocorp, Ipmax, DrReddy, and Zosano. Dr. Goadsby has received research support from Amgen Inc., Merck Sharp & Dohme Limited, and Allergan, Inc. Dr. Seeley has nothing to disclose.