title: Beta-coupled high-frequency activity and beta-locked neuronal spiking in the subthalamic nucleus of Parkinson's disease.
abstract: Beta frequency (13-30 Hz) oscillatory activity in the subthalamic nucleus (STN) of Parkinson's disease (PD) has been shown to influence the temporal dynamics of high-frequency oscillations (HFOs; 200-500 Hz) and single neurons, potentially compromising the functional flexibility of the motor circuit. We examined these interactions by simultaneously recording both local field potential and single-unit activity from the basal ganglia of 15 patients with PD during deep brain stimulation (DBS) surgery of the bilateral STN. Phase-amplitude coupling (PAC) in the STN was specific to beta phase and HFO amplitude, and this coupling was strongest at the dorsal STN border. We found higher beta-HFO PAC near DBS lead contacts that were clinically effective compared with the remaining non-effective contacts, indicating that PAC may be predictive of response to STN DBS. Neuronal spiking was locked to the phase of 8-30 Hz oscillations, and the spatial topography of spike-phase locking (SPL) was similar to that of PAC. Comparisons of PAC and SPL showed a lack of spatiotemporal correlations. Beta-coupled HFOs and field-locked neurons had different preferred phase angles and did not co-occur within the same cycle of the modulating oscillation. Our findings provide additional support that beta-HFO PAC may be central to the pathophysiology of PD and suggest that field-locked neurons alone are not sufficient for the emergence of beta-coupled HFOs.
authors.affiliation: Surgical Neurology Branch.
authors.forename: Andrew I
authors.initials: AI
authors.lastname: Yang
authors.affiliation: Office of the Clinical Director, and Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: Nora
authors.identifier: http://orcid.org/0000-0002-5073-4024
authors.initials: N
authors.lastname: Vanegas
authors.affiliation: Office of the Clinical Director, and.
authors.forename: Codrin
authors.identifier: http://orcid.org/0000-0001-6253-3281
authors.initials: C
authors.lastname: Lungu
authors.affiliation: Surgical Neurology Branch, kareem.zaghloul@nih.gov.
authors.forename: Kareem A
authors.initials: KA
authors.lastname: Zaghloul
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D001479:Basal Ganglia / Q000502:physiology; D001611:Beta Rhythm / Q000502:physiology*; D058256:Brain Waves / Q000502:physiology*; D046690:Deep Brain Stimulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000502:physiology*; D010300:Parkinson Disease / Q000503:physiopathology* / Q000601:surgery; D012720:Severity of Illness Index; D020531:Subthalamic Nucleus / Q000503:physiopathology* / Q000601:surgery
keywords: Parkinson's disease; beta oscillations; cross-frequency interactions; high-frequency oscillations; spike-field interactions; subthalamic nucleus