FIG. 1.

Upper row (1) patient 1: (A) FDG‐PET 3D‐stereotactic surface projection (3D‐SSP, software cortex ID suite, GE Healthcare): asymmetric frontoparietal hypometabolism, including the sensory and motor cortex, worst on the left side. PIB‐PET 3D‐SSP (B) negative for amyloid deposition, and T₁‐weighted MRI (C) with asymmetric frontoparietal atrophy, also worst on the left (red arrows). Lower row (2) patient 2: (C) FDG‐PET 3D‐SSP: asymmetric posterior temporoparietal hypometabolism, also including the sensory and motor cortex, worst on the left side. PIB‐PET 3D‐SSP (E) positive for diffuse cortical amyloid deposition, and T₁‐weighted MRI (F) showing bilateral parietal cortical atrophy (red arrows). The white arrows on A and D point to the supplementary motor cortex, probably related to the synkinesis.