title: The oscillatory activity in the Parkinsonian subthalamic nucleus investigated using the macro-electrodes for deep brain stimulation.
abstract: OBJECTIVE
  To investigate the oscillatory activity in the Parkinsonian subthalamic nucleus using the macro-electrodes for deep brain stimulation.
  
  
  METHODS
  During bilateral deep brain stimulating electrode implantation, spontaneous and evoked field potentials were recorded from the subthalamic nucleus (STN) in two patients with Parkinson's disease (PD) during spontaneous resting tremor, passive manipulation of the wrist, and following electrical stimulation of the contralateral STN.
  
  
  RESULTS
  Frequency analysis of the STN field potentials recorded during spontaneous resting tremor showed significant coherence with electromyographic activity in the contralateral arm, suggesting a close involvement of the STN in the generation of resting tremor in PD. The STN responded to passive movement of the contralateral wrist, but not to ipsilateral movement. High frequency (100 Hz) electrical stimulation of the STN induced tremor (4 Hz) in both forearms, and also oscillation of the contralateral STN (4 Hz). In contrast, low frequency (5 Hz) stimulation induced contralateral arrhythmic involuntary movement (3 Hz), but without altering the contralateral STN activity.
  
  
  CONCLUSIONS
  We propose that the functional connection between the STN and arm muscles is mainly contralateral, but cross talk may occur between bilateral STN via a frequency-dependent pathway.
authors.affiliation: University Laboratory of Physiology, University of Oxford, Parks Road, Oxford OX1 3PT, UK. xl@physiol.ox.ac.uk
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: H L
authors.initials: HL
authors.lastname: Ford-Dunn
authors.forename: G N
authors.initials: GN
authors.lastname: Hayward
authors.forename: D
authors.initials: D
authors.lastname: Nandi
authors.forename: R C
authors.initials: RC
authors.lastname: Miall
authors.forename: T Z
authors.initials: TZ
authors.lastname: Aziz
authors.forename: J F
authors.initials: JF
authors.lastname: Stein
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D004576:Electromyography; D005071:Evoked Potentials / Q000502:physiology; D005542:Forearm / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D018482:Muscle, Skeletal / Q000503:physiopathology; D009434:Neural Pathways / Q000503:physiopathology; D010300:Parkinson Disease / Q000503:physiopathology*; D051381:Rats; D020531:Subthalamic Nucleus / Q000503:physiopathology*; D014202:Tremor / Q000503:physiopathology