title: Subthalamic nucleus long-range synchronization-an independent hallmark of human Parkinson's disease.
abstract: Beta-band synchronous oscillations in the dorsolateral region of the subthalamic nucleus (STN) of human patients with Parkinson's disease (PD) have been frequently reported. However, the correlation between STN oscillations and synchronization has not been thoroughly explored. The simultaneous recordings of 2390 multi-unit pairs recorded by two parallel microelectrodes (separated by fixed distance of 2 mm, n = 72 trajectories with two electrode tracks >4 mm STN span) in 57 PD patients undergoing STN deep brain stimulation surgery were analyzed. Automatic procedures were utilized to divide the STN into dorsolateral oscillatory and ventromedial non-oscillatory regions, and to quantify the intensity of STN oscillations and synchronicity. Finally, the synchronicity of simultaneously vs. non-simultaneously recorded pairs were compared using a shuffling procedure. Synchronization was observed predominately in the beta range and only between multi-unit pairs in the dorsolateral oscillatory region (n = 615). In paired recordings between sites in the dorsolateral and ventromedial (n = 548) and ventromedial-ventromedial region pairs (n = 1227), no synchronization was observed. Oscillation and synchronicity intensity decline along the STN dorsolateral-ventromedial axis suggesting a fuzzy border between the STN regions. Synchronization strength was significantly correlated to the oscillation power, but synchronization was no longer observed following shuffling. We conclude that STN long-range beta oscillatory synchronization is due to increased neuronal coupling in the Parkinsonian brain and does not merely reflect the outcome of oscillations at similar frequency. The neural synchronization in the dorsolateral (probably the motor domain) STN probably augments the pathological changes in firing rate and patterns of subthalamic neurons in PD patients.
authors: Department of Medical Neurobiology, IMRIC, The Hebrew University-Hadassah Medical School Jerusalem, Israel ; The Interdisciplinary Center for Neural Computation, The Hebrew University Jerusalem, Israel ; The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University Jerusalem, Israel ; The Research Laboratory of Brain Imaging and Stimulation, The Jerusalem Mental Health Center, Kfar-Shaul Etanim, Hebrew University-Hadassah Medical School Jerusalem, Israel.
authors: Shay
authors: S
authors: Moshel
authors: Reuben R
authors: RR
authors: Shamir
authors: Aeyal
authors: A
authors: Raz
authors: Fernando R
authors: FR
authors: de Noriega
authors: Renana
authors: R
authors: Eitan
authors: Hagai
authors: H
authors: Bergman
authors: Zvi
authors: Z
authors: Israel
keywords: Parkinson's disease; deep brain stimulation; oscillations; subthalamic nucleus; synchronization