Cerebral metabolic consequences of electrical cutaneous stimulation in normal individuals

Local cerebral uptake of deoxyglucose labeled with fluorine (FDG) was measured by positron emission tomography in 21 normal adult controls. Seven subjects received FDG while resting in a dark room and fourteen while receiving unpleasant electrical stimulation of their right forearm in a dark room. All subjects showed greater glucose use in the anterior than in the posterior cerebral cortex. Electrical stimulation of the right forearm was associated with greater left than right glucose use in the region of the postcentral, but not precentral gyrus. The antero-posterior gradient in glucose use was increased at the level of the inferior frontal gyrus by the electrical stimulation. The data are consistent with the hyperfrontal pattern reported for regional cerebral blood flow and suggest that glucose use gradients across large brain areas are sensitive to sensory stimulation.