ACHE and Parkinson disease: This denervation topography is consistent with previous cholinergic imaging studies, which described predominantly posterior and temporal cortical binding differences between Parkinson’s disease patients and healthy controls.16,21,44,45 These studies generally focused on more advanced Parkinson’s disease subjects, though one small study using acetylcholinesterase PET identified some Parkinson’s disease subjects with early loss of cholinergic synapses.44 Our results suggest that GBA-PD exhibits accelerated degeneration of especially nucleus basalis of Meynert (Ch4) projections neurons.