Fig. 1.

Magnetoencephalography (MEG) waveforms showing neuromagnetic activation evoked by right median nerve stimulation in a migraine subject (“Migraine”) and a healthy subject (“Control”) in a frequency band of 30–80 Hz. There are at least two responses in the somatosensory-evoked magnetic fields (SEFs), “SEFs1” and “SEFs2”. Our analyzed time window is 10-40 ms, which contained the two main responses under somatosensory stimulation. The “Trigger” indicates the start of median nerve stimuli. The “SEFs1” and “SEFs2” indicate the first and second SEF responses, respectively