title: Dopamine replacement modulates oscillatory coupling between premotor and motor cortical areas in Parkinson's disease.
abstract: Efficient neural communication between premotor and motor cortical areas is critical for manual motor control. Here, we used high-density electroencephalography to study cortical connectivity in patients with Parkinson's disease (PD) and age-matched healthy controls while they performed repetitive movements of the right index finger at maximal repetition rate. Multiple source beamformer analysis and dynamic causal modeling were used to assess oscillatory coupling between the lateral premotor cortex (lPM), supplementary motor area (SMA), and primary motor cortex (M1) in the contralateral hemisphere. Elderly healthy controls showed task-related modulation in connections from lPM to SMA and M1, mainly within the γ-band (>30 Hz). Nonmedicated PD patients also showed task-related γ-γ coupling from lPM to M1, but γ coupling from lPM to SMA was absent. Levodopa reinstated physiological γ-γ coupling from lPM to SMA and significantly strengthened coupling in the feedback connection from M1 to lPM expressed as β-β as well as θ-β coupling. Enhancement in cross-frequency θ-β coupling from M1 to lPM was correlated with levodopa-induced improvement in motor function. The results show that PD is associated with an altered neural communication between premotor and motor cortical areas, which can be modulated by dopamine replacement.
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany, Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.
authors.forename: Damian Marc
authors.initials: DM
authors.lastname: Herz
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany, Cognitive Neurology Section, Institute of Neurosciences and Medicine (INM-3), Research Centre Juelich, Juelich, Germany, McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
authors.forename: Esther
authors.initials: E
authors.lastname: Florin
authors.affiliation: Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark, Department of Nutrition, Exercise and Sports, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark and.
authors.forename: Mark Schram
authors.initials: MS
authors.lastname: Christensen
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Reck
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany, Cognitive Neurology Section, Institute of Neurosciences and Medicine (INM-3), Research Centre Juelich, Juelich, Germany.
authors.forename: Michael Thomas
authors.initials: MT
authors.lastname: Barbe
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany.
authors.forename: Maike Karoline
authors.initials: MK
authors.lastname: Tscheuschler
authors.affiliation: Max Planck Institute for Neurological Research, Cologne, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Tittgemeyer
authors.affiliation: Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.
authors.forename: Hartwig Roman
authors.initials: HR
authors.lastname: Siebner
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Timmermann
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use; D001499:Bayes Theorem; D058256:Brain Waves / Q000502:physiology*; D016022:Case-Control Studies; D046690:Deep Brain Stimulation; D004569:Electroencephalography; D004576:Electromyography; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007980:Levodopa / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging; D008297:Male; D008750:Methyldopa / Q000378:metabolism*; D008875:Middle Aged; D009044:Motor Cortex / Q000098:blood supply / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000294:innervation; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D010100:Oxygen / Q000097:blood; D010300:Parkinson Disease / Q000473:pathology* / Q000628:therapy; D013997:Time Factors
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa; D008750:Methyldopa; D010100:Oxygen
keywords: dynamic causal modeling (DCM); effective connectivity; electroencephalography (EEG); neural communication