Real Time Analyses of Electrophysiological Mechanisms of Freezing of Gait in Parkinson's Disease Patient during Deep Brain Stimulation Surgery by Using a Novel Portable Multi-Functional Electrophysiological Experiment Platform

Parkinson’s disease is a neurodegenerative disease due to the degeneration of dopaminergic neurons in the substantia nigra pars compacta of the midbrain that projects to the basal ganglia. The main motor impairments are tremor, rigidity, bradykinesia and gait disturbance. In Parkinson’s disease, gait disturbance and balance deficits are mainly characterized by gait akinesia, freezing of gait (FoG) and postural instability with falls. FoG typically lasts for a few seconds and is associated to a unique sensation: the patients feel that his feet are glued to the ground, blocking them despite effort to move forward. FoG is reported by 48% to 70% of PD patients 5 years after the onset of disease. The appearance of FoG is an indicator of disease severity and delay of survival. Levodopa and deep brain stimulation at subthalamic nucleus (STN) ameliorate motor symptoms of PD. However, FoG is more resistant to medicine or electric stimulation therapy. The pathophysiological mechanism of FoG in PD remains unclear. Local field potentials (LFPs) recorded from STN electrodes in PD patients have demonstrated correlations between neuronal synchronization and disease severity. However, this correlation is only seen in bradykinesia-rigidity but not in gait disturbance. There are several possibilities. The clinical evaluation hardly reflects the nature contest of FoG. More importantly, There are very few studies using real time recording of neuronal activities while patients are experiencing FoG. This has impeded the progress of research and therapy for gait disturbance in PD. In this study, we will explore the electrophysiological mechanism of FoG in PD by using a novel portable multi-functional electrophsiological experiment platform. To this end, we will assess the real time LFPs and EEG from parkinsonian patients implanted with STN electrodes and investigate the pattern of neuronal activity in this region and its relationship to the performance of gait.

Project ID:PC10301-0085
External Project ID:NSC102-2923-B182-001-MY3