"How does the brain process noxious stimuli, and how does this lead to the perception of pain? Human electrophysiological studies using electroencephalography (EEG) or magnetoencephalography (MEG), as well as studies using functional magnetic resonance imaging (fMRI) or positron emission tomography (PET), have all shown that noxious stimuli, or painful stimuli, elicit neural responses in a vast ar ...