SV2A and red-green color blindness: In PSP patients, the loss of SV2A has recently been reported in the medulla, substantia nigra, pallidum, midbrain, pons and caudate nucleus, with greatest SV2A loss in the medulla, hippocampus, amygdala, caudate, insula and thalamus in CBD patients with amyloid-β-negative (11C)PIB PET scans [193].