Fig. 2From: Altered effective connectivity in migraine patients during emotional stimuli: a multi-frequency magnetoencephalography studyMagnetoencephalography (MEG) waveforms, showing neuromagnetic activation upon exposure to emotional stimuli in a migraine subject and a healthy subject in the 8–12 Hz frequency range. “M1” and “M2” were the two main components evoked by human facial expressions. The “Trigger” indicates the start of emotional stimuliBack to article page