title: The effects of unilateral versus bilateral subthalamic nucleus deep brain stimulation on prosaccades and antisaccades in Parkinson's disease.
abstract: Unilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) in patients with Parkinson's disease improves skeletomotor function assessed clinically, and bilateral STN DBS improves motor function to a significantly greater extent. It is unknown whether unilateral STN DBS improves oculomotor function and whether bilateral STN DBS improves it to a greater extent. Further, it has also been shown that bilateral, but not unilateral, STN DBS is associated with some impaired cognitive-motor functions. The current study compared the effect of unilateral and bilateral STN DBS on sensorimotor and cognitive aspects of oculomotor control. Patients performed prosaccade and antisaccade tasks during no stimulation, unilateral stimulation, and bilateral stimulation. There were three sets of findings. First, for the prosaccade task, unilateral STN DBS had no effect on prosaccade latency and it reduced prosaccade gain; bilateral STN DBS reduced prosaccade latency and increased prosaccade gain. Second, for the antisaccade task, neither unilateral nor bilateral stimulation had an effect on antisaccade latency, unilateral STN DBS increased antisaccade gain, and bilateral STN DBS increased antisaccade gain to a greater extent. Third, bilateral STN DBS induced an increase in prosaccade errors in the antisaccade task. These findings suggest that while bilateral STN DBS benefits spatiotemporal aspects of oculomotor control, it may not be as beneficial for more complex cognitive aspects of oculomotor control. Our findings are discussed considering the strategic role the STN plays in modulating information in the basal ganglia oculomotor circuit.
authors.affiliation: Department of Kinesiology and Nutrition, University of Illinois, 901 West Roosevelt, Chicago, IL, 60612, USA. lchin1@uic.edu.|Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, USA. lchin1@uic.edu.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Goelz
authors.affiliation: Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, USA.
authors.forename: Fabian J
authors.initials: FJ
authors.lastname: David
authors.affiliation: Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Sweeney
authors.affiliation: Departments of Applied Physiology and Kinesiology, Biomedical Engineering, and Neurology, University of Florida, Gainesville, FL, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Vaillancourt
authors.affiliation: Institute for Neural Computation, University of California, San Diego, CA, USA.
authors.forename: Howard
authors.initials: H
authors.lastname: Poizner
authors.affiliation: Department of Neurological Sciences, Section of Parkinson Disease and Movement Disorders, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Leonard Verhagen
authors.initials: LV
authors.lastname: Metman
authors.affiliation: Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, USA.|Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Corcos
mesh_terms: D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology* / Q000628:therapy*; D011930:Reaction Time / Q000502:physiology; D020531:Subthalamic Nucleus / Q000502:physiology*; D013997:Time Factors
keywords: Deep brain stimulation; Parkinson disease; STN DBS; Saccade; Subthalamic nucleus