MAPT and Parkinson disease: Current research suggests that the development of cognitive impairment in PD is associated with a number of factors, such as the build-up of beta-amyloid and tau proteins in the central nervous system, oxidative stress, neuroinflammation, traumatic brain injury, environmental factors (e.g., pesticide and tobacco exposure), and genetic risk factors (including genes such as COMT, APOE, MAPT, and BDNF) (Gonzalez-Latapi et al., 2021).