ATP1A2 and Salla disease: In patients, loss-of-function mutations in the ATP1A2 gene cause FHM2, which is clinically characterized by complicated migraine auras.36,76,116 Direct clinical evidence from ECoG recordings117 and indirect evidence from measurements of rCBF or its surrogates18,118,119 suggest that migraine aura is one of the clinical manifestations of SD.