LB and amyloid plaque pathologies in cortical and limbic regions are highly associated with the occurrence of dementia in the clinical course of PD4,5,21, and the patients with PD dementia were more likely to show lower CSF Aβ1-42 and higher CSF t-tau and p-tau levels, when compared to those with normal cognition22–24. Here, MAPT is linked to dementia.