title: Movement-related frequency modulation of beta oscillatory activity in the human subthalamic nucleus.
abstract: Event-related changes of brain electrical rhythms are typically analysed as amplitude modulations of local field potential (LFP) oscillations, like radio amplitude modulation broadcasting. In telecommunications, frequency modulation (FM) is less susceptible to interference than amplitude modulation (AM) and is therefore preferred for high-fidelity transmissions. Here we hypothesized that LFP rhythms detected from deep brain stimulation (DBS) electrodes implanted in the subthalamic nucleus (STN) in patients with Parkinson's disease could represent movement-related activity not only in AM but also in FM. By combining adaptive autoregressive identification with spectral power decomposition, we were able to show that FM of low-beta (13-20 Hz) and high-beta (20-35 Hz) rhythms significantly contributes to the involvement of the human STN in movement preparation, execution and recovery, and that the FM patterns are regulated by the dopamine levels in the system. Movement-related FM of beta oscillatory activity in the human subthalamic nucleus therefore provides a novel informational domain for rhythm-based pathophysiological models of cortico-basal ganglia processing.
authors.affiliation: Dipartimento di Scienze Neurologiche, Università di Milano, Fondazione IRCCS Ospedale Policlinico, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Foffani
authors.forename: A M
authors.initials: AM
authors.lastname: Bianchi
authors.forename: G
authors.initials: G
authors.lastname: Baselli
authors.forename: A
authors.initials: A
authors.lastname: Priori
mesh_terms: D000328:Adult; D000368:Aged; D001611:Beta Rhythm; D015259:Dopamine Agents / Q000627:therapeutic use; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology*; D020531:Subthalamic Nucleus / Q000503:physiopathology*
chemical_list: D015259:Dopamine Agents; D007980:Levodopa