FIGURE 2.  (A) Plots of Polaris translation files (X, left–right; Y, anterior/posterior; Z, dorsal/ventral): x-axis time = min; y-axis from an arbitrary starting point = mm. a and b indicate large movements. (B) Time–activity curve and PET summated images of (from top to bottom): raw PET data, FBF realignment, MTfbf realignment, MT realignment, and LMCfbf realignment. CB = cerebellum; x-axis time = min; y-axis activity = kBq/mL.