Quantification of α-synuclein pathology in the hippocampus (HC) of control subjects, iLBD cases and PD patients. (a) Significant differences were present in α-synuclein deposits between all pyramidal subregions of the HC in the PD patients (*p < 0.05). The CA2 region was affected the most relative to the other hippocampal subregions (#p < 0.01). (b) Comparison of α-synuclein pathology in CA2 between the three patient cohorts showed a significant increase in the PD patients compared to control and iLBD cases (*p < 0.01 vs iLBD, Ctr). Data represent mean ± SEM.