Patients with neuropathic pain exhibit hyperalgesia and allodynia. Although both peripheral and central determinants are recognized for the pathophysiological basis of neuropathic pain following peripheral injury, the modulating effect on pain processing in brain by peripheral mechanisms remains elusive. Here, we will systematically compare the sensory symptoms and brain activation to innocuous and noxious thermal stimulation applied to the distal leg, foot dorsum or forearm between patients with peripheral neuropathy and healthy controls. Functional magnetic resonance imaging will be used to define brain activation to somatic stimulation with noxious and innocuous stimuli. The blood-oxygenation-level-dependent signals will be correlated with visual analogue scale scores and sensory and affective components obtained from the Short-Form McGill Pain Questionnaire. Brain activation during thermal stimulation in patients with neuropathic pain will be clarified, and we will also analyze the potential relationships between the topography, quality and intensity of the different painful symptoms (i.e. spontaneous ongoing pain, paroxysmal pain, allodynia, hyperalgesia) and the magnitude and pattern of brain activation during thermal stimulation. This will add in our understanding in the pathophysiology of brain modulation in pain and provide clinically useful message toward the potential therapeutics in the management of neuropathic pain.