Pallidal beta bursts in Parkinson's disease and dystonia

BACKGROUND: Exaggerated beta power has been discussed as a disease-specific biomarker for Parkinson's disease (PD) and has recently been suggested to rely on prolonged bursts of subthalamic beta synchronization. OBJECTIVE: In this study, we test whether prolonged bursts are disease specific for beta activity in PD by comparison to oscillatory activity in dystonia. METHODS: Pallidal local field potentials were recorded from 5 PD patients ON and OFF dopaminergic medication and 5 dystonia patients. Synchronization of beta and low-frequency oscillations in bursts was compared between groups with respect to their duration, amplitude, and rate. RESULTS: Pallidal beta bursts were longer in PD-OFF than PD-ON or dystonia (P < .05). PD-ON and dystonia displayed similar beta burst dynamics. Low-frequency burst features showed no differences across groups. CONCLUSIONS: Prolonged burst duration appears as a disease-specific feature for beta activity in PD across the basal ganglia. With dopaminergic medication, beta bursts in PD resemble those in dystonia, which supports the notion of short beta bursts as a physiological pattern. © 2018 International Parkinson and Movement Disorder Society.