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The Role of the Cerebellum in the Pathophysiology of Parkinson's Disease

Published online by Cambridge University Press:  23 September 2014

Mechelle M. Lewis
Affiliation:
Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA
Shawna Galley
Affiliation:
Pacific Parkinson's Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
Samantha Johnson
Affiliation:
Pacific Parkinson's Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
James Stevenson
Affiliation:
Pacific Parkinson's Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
Xuemei Huang
Affiliation:
Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA Department of Radiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA Department of Neurosurgery, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA Department of Kinesiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA Department of Bioengineering, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA, USA
Martin J. McKeown*
Affiliation:
Pacific Parkinson's Research Centre, University of British Columbia, Vancouver, British Columbia, Canada Department of Medicine (Neurology), University of British Columbia, Vancouver, British Columbia, Canada Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia, Canada
*
Neurology, Pacific Parkinson's Research Centre, Brain Research Centre, University of British Columbia, M31, Purdy Pavillion, Vancouver, British Columbia, V6T 2B5, Canada. Email: martin.mckeown@ubc.edu
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Abstract

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Parkinson's disease (PD), the most common neurodegenerative movement disorder, has traditionally been considered a “classic” basal ganglia disease, as the most obvious pathology is seen in the dopaminergic cells in the substantia nigra pars compacta. Nevertheless recent discoveries in anatomical connections linking the basal ganglia and the cerebellum have led to a re-examination of the role of the cerebellum in the pathophysiology of PD. This review summarizes the role of the cerebellum in explaining many curious features of PD: the significant variation in disease progression between individuals; why severity of dopaminergic deficit correlates with many features of PD such as bradykinesia, but not tremor; and why PD subjects with a tremor-predominant presentation tend to have a more benign prognosis. It is clear that the cerebellum participates in compensatory mechanisms associated with the disease and must be considered an essential contributor to the overall pathophysiology of PD.

Résumé:

Résumé:

La Maladie de Parkinson (MP), le trouble du mouvement de nature neurodégénérative le plus fréquent, a traditionnellement été considérée comme une maladie « classique » des noyaux gris centraux, étant donné que la pathologie la plus évidente se retrouve dans les cellules dopaminergiques de la substance noire de la pars compacta. Néanmoins, des découvertes récentes concernant les connections anatomiques liant les noyaux gris centraux et le cervelet ont mené à un nouvel examen du rôle du cervelet dans la physiopathologie de la MP. Cette revue explique de façon résumée plusieurs aspects singuliers de la MP dans lesquels le cervelet joue un rôle : la variation importante dans la progression de la maladie entre les patients ; pourquoi la sévérité du déficit dopaminergique est en corrélation avec plusieurs manifestations de la MP telle la bradykinésie, mais non avec le tremblement ; et pourquoi les patients chez qui le tremblement prédomine ont tendance à avoir un meilleur pronostic. il est certain que le cervelet participe à des mécanismes compensatoires associés à la maladie et sa contribution doit être considérée comme essentielle à la physiopathologie globale de la MP.

Type
Review Article
Copyright
Copyright © The Canadian Journal of Neurological 2013

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