Figure reprinted with permission: Huang C, Tang C, Feigin A, et al. Changes in network activity with the progression of Parkinson’s disease. Brain 2007; 130(7):1834–1846. (A) Voxel-based analysis of longitudinal changes in regional metabolic activity. Metabolic increases with disease progression are displayed using a red–yellow scale. Progressive metabolic declines are displayed using a blue–purple scale. (B) Displays of the metabolic data for these individual regions at each timepoint. The coordinates refer to the Montreal Neurological Institute (MNI) standard space. Abbreviations: GPi = internal globus pallidus, STN = subthalamic nucleus, BA = Brodmann area.