Interrelations between cognitive dysfunction and motor symptoms of Parkinson’s disease: behavioral and neural studies

Ahmed A. Moustafa, Srinivasa Chakravarthy 3 , Joseph R. Phillips 4 , Jacob J. Crouse 4 , Ankur Gupta 3 , Michael J. Frank 5 , Julie M. Hall 4 , and Marjan Jahanshahi 6
  • 1 School of Social Sciences and Psychology and Marcs Institute for Brain and Behaviour, Western Sydney University, Sydney, New South Wales 2214, Australia
  • 2 Department of Veterans Affairs, New Jersey Health Care System, East Orange, NJ 07018, USA
  • 3 Department of Biotechnology, Indian Institute of Technology, Madras, Chennai 600 036, India
  • 4 School of Social Sciences and Psychology, Western Sydney University, Sydney, New South Wales, Australia
  • 5 Department of Cognitive, Linguistic Sciences and Psychological Sciences, Brown Institute for Brain Science, Brown University, Providence, RI 02912, USA
  • 6 Cognitive Motor Neuroscience Group and Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, The National Hospital for Neurology and Neurosurgery, London, WC1N 3BG, UK
Ahmed A. Moustafa, Srinivasa Chakravarthy, Joseph R. Phillips, Jacob J. Crouse, Ankur Gupta, Michael J. Frank, Julie M. Hall and Marjan Jahanshahi

Abstract

Parkinson’s disease (PD) is characterized by a range of motor symptoms. Besides the cardinal symptoms (tremor, bradykinesia/akinesia, and rigidity), PD patients also show other motor deficits, including gait disturbance, speech deficits, and impaired handwriting. However, along with these key motor symptoms, PD patients also experience cognitive deficits in attention, executive function, working memory, and learning. Recent evidence suggests that these motor and cognitive deficits of PD are not completely dissociable, as aspects of cognitive dysfunction can impact motor performance in PD. In this article, we provide a review of behavioral and neural studies on the associations between motor symptoms and cognitive deficits in PD, specifically akinesia/bradykinesia, tremor, gait, handwriting, precision grip, and speech production. This review paves the way for providing a framework for understanding how treatment of cognitive dysfunction, for example cognitive rehabilitation programs, may in turn influence the motor symptoms of PD.

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