Abstract
Since pain is a subjective experience comprising unpleasant sensation and affection, the objective assessment of pain has been difficult. Recent brain imaging methods, such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), magnetic resonance spectroscopy (MRS), and voxel-based morphometry (VBM) have identified the brain regions involved in the pain-related neural network. Many noninvasive brain imaging studies have revealed that chronic pain patients have functional, chemical, and structural changes in different areas of the brain related to emotional and cognitive dimension of pain. We review the literature of brain imaging and latest knowledge regarding the central mechanism of pain.
