Hitoshi Shimada, MD, PhD, National Institute of Radiological Sciences, Chiba, Japan, talks on neuroimaging studies that have investigated the role of non-dopaminergic neurodegeneration in the clinical manifestations of Parkinson’s disease (PD). While PD is well recognized as a neurodegenerative disorder characterized by loss of dopaminergic neurons, various lines of evidence implicate non-dopaminergic pathways as significant contributors to certain disease features. Dr Shimada discusses evidence from neuroimaging studies and explains how they support the hypothesis that non-dopaminergic systems such as the cholinergic system play a role in symptoms of PD. PET imaging studies have shown that PD patients have a clear decrease in cholinergic activity, predominantly in the medial region of the occipital lobe. Another PET study investigating the association between regional vesicular acetylcholine transporter (VAChT) expression and freezing of gait and falls found that cholinergic systems changes were associated with both symptoms. This interview took place during the 2021 International Congress of Parkinson’s Disease and Movement Disorders.
Dr Shimada holds patents on compounds related to the present presentation (JP 5422782/EP 12 884 742.3/CA2894994/HK1208672).