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Experimental Brain Research

, Volume 206, Issue 1, pp 1–13 | Cite as

Event-related desynchronization of motor cortical oscillations in patients with multiple system atrophy

  • Ron Levy
  • Andres M. Lozano
  • Anthony E. Lang
  • Jonathan O. DostrovskyEmail author
Research Article

Abstract

Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by parkinsonism (MSA-P), cerebellar and autonomic deficits. In Parkinson’s disease (PD), an impaired modulation of motor cortical mu and beta range oscillations may be related to the pathophysiology of bradykinesia. Event-related desynchronization (ERD) of these oscillations occur for 1–2 s preceding a voluntary movement in normal subjects and patients with PD treated with levodopa while only lasting around 0.5 s in untreated patients. Motor cortical rhythms were recorded from subdural strip electrodes in three patients with MSA-P while taking their regular dopaminergic medications. Following a ready cue, patients performed an externally cued wrist extension movement to a go cue. In addition, recordings were obtained during imagined wrist extension movements to the same cues and during self-paced wrist extensions. ERD and event-related synchronization were examined in subject-specific frequency bands. All patients showed movement-related ERD in subject-specific frequency bands below ~40 Hz in both externally cued and self-paced conditions. Preparatory ERD latency preceding self-cued movement was 900 ms in one patient and at or after movement onset in the other two patients. In the externally cued task, a short lasting (<1.3 s) ready cue-related ERD that was not sustained to movement onset was observed in two patients. Imagined movements resulted in go cue-related ERD with a smaller magnitude in the same two patients. These results indicate that the modulation of motor cortical oscillations in patients with MSA that are treated with levodopa is similar to that occurring in untreated patients with PD. The findings suggest that cortical activation in patients with MSA is diminished, may be related to pathophysiological changes occurring in the basal ganglia and correlates with the poor clinical response that these patients typically obtain with dopaminergic therapy.

Keywords

Multiple system atrophy Parkinson’s disease Event-related desynchronization Mu rhythm Beta rhythm 

Abbreviations

MSA

Multiple system atrophy

MSA-P

MSA with parkinsonian symptoms

ECoG

Electrocorticography

EMG

Electromyographic

PD

Parkinson’s disease

ERD

Event-related desynchronization

ERS

Event-related synchronization

UPDRS

United Parkinson’s disease rating scale

MRI

Magnetic resonance imaging

STN

Subthalamic nucleus

Notes

Acknowledgments

We thank Dr. Peter Ashby from the Toronto Western Research Institute for assistance with the electrophysiological recordings. Funding was provided by grants from the Canadian Institutes of Health Research MOP 42505 and US NIH DE40872 to JOD. AML is a Tier 1 Canada Research Chair in Neuroscience.

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Ron Levy
    • 1
  • Andres M. Lozano
    • 2
    • 3
  • Anthony E. Lang
    • 2
    • 4
  • Jonathan O. Dostrovsky
    • 2
    • 5
    Email author
  1. 1.Division of Neurosurgery, Department of Clinical Neuroscience, Faculty of MedicineUniversity of Calgary, Foothills Medical CentreCalgaryCanada
  2. 2.The Toronto Western Research InstituteTorontoCanada
  3. 3.Department of Surgery, University of Toronto, Division of NeurosurgeryThe Toronto Western HospitalTorontoCanada
  4. 4.Department of Medicine, University of Toronto, Division of NeurologyThe Toronto Western HospitalTorontoCanada
  5. 5.Department of Physiology, Faculty of MedicineUniversity of TorontoTorontoCanada

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