Network dynamics in Parkinson's disease: Primate models and patients

Advances in electrophysiological recording techniques have enabled investigations into neuronal activity at the level of single neurons and local field potentials and led to new insights into the pathophysiology of Parkinson's disease (PD). Neural oscillatory activity in the beta frequency band has been observed across the basal ganglia thalamocortical (BGTC) network and associated with PD symptoms. While changes in neuronal firings and resting state beta oscillatory power in cortex have varied across studies, excessive beta power in basal ganglia and abnormal neuronal modulation during tasks have been consistently observed in patients and nonhuman primate models of PD. Altered interaction across regions in the BGTC circuit might also be a reliable biomarker for PD, supporting the idea that PD is a network disorder. Observation of these neural changes in the early stage of the disease also enhances our understanding of the pathophysiology and inspires early diagnosis or intervention for PD.