title: Effect of subthalamic nucleus deep brain stimulation on dual-task cognitive and motor performance in isolated dystonia.
abstract: OBJECTIVE
  Subthalamic nucleus (STN) deep brain stimulation (DBS) can improve motor complications of Parkinson's disease (PD) but may worsen specific cognitive functions. The effect of STN DBS on cognitive function in dystonia patients is less clear. Previous reports indicate that bilateral STN stimulation in patients with PD amplifies the decrement in cognitive-motor dual-task performance seen when moving from a single-task to dual-task paradigm. We aimed to determine if the effect of bilateral STN DBS on dual-task performance in isolated patients with dystonia, who have less cognitive impairment and no dementia, is similar to that seen in PD.
  
  
  METHODS
  Eight isolated predominantly cervical patients with dystonia treated with bilateral STN DBS, with average dystonia duration of 10.5 years and Montreal Cognitive Assessment score of 26.5, completed working memory (n-back) and motor (forced-maintenance) tests under single-task and dual-task conditions while on and off DBS.
  
  
  RESULTS
  A multivariate, repeated-measures analysis of variance showed no effect of stimulation status (On vs Off) on working memory (F=0.75, p=0.39) or motor function (F=0.22, p=0.69) when performed under single-task conditions, though as working memory task difficulty increased, stimulation disrupted the accuracy of force-tracking. There was a very small worsening in working memory performance (F=9.14, p=0.019) when moving from single-task to dual-tasks when using the 'dual-task loss' analysis.
  
  
  CONCLUSIONS
  This study suggests the effect of STN DBS on working memory and attention may be much less consequential in patients with dystonia than has been reported in PD.
authors.affiliation: Department of Neurology, University of California, San Francisco, California, USA Parkinson's Disease Research, Education, and Clinical Center, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA.
authors.forename: Kelly A
authors.identifier: http://orcid.org/0000-0002-4302-1501
authors.initials: KA
authors.lastname: Mills
authors.affiliation: Department of Neurology, University of California, San Francisco, California, USA.
authors.forename: Leslie C
authors.initials: LC
authors.lastname: Markun
authors.affiliation: Department of Neurology, University of California, San Francisco, California, USA.
authors.forename: Marta
authors.initials: M
authors.lastname: San Luciano
authors.affiliation: Department of Biomedical Engineering, Cleveland Clinic, Cleveland, Ohio, USA.
authors.forename: Rami
authors.initials: R
authors.lastname: Rizk
authors.affiliation: Department of Epidemiology & Biostatistics, University of California San Francisco, San Francisco, California, USA.
authors.forename: I Elaine
authors.initials: IE
authors.lastname: Allen
authors.affiliation: Department of Neurosurgery, University of California San Francisco, San Francisco, California, USA.
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Racine
authors.affiliation: Department of Neurosurgery, University of California San Francisco, San Francisco, California, USA.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Starr
authors.affiliation: Department of Biomedical Engineering, Cleveland Clinic, Cleveland, Ohio, USA.
authors.forename: Jay L
authors.initials: JL
authors.lastname: Alberts
authors.affiliation: Department of Neurology, University of California, San Francisco, California, USA Parkinson's Disease Research, Education, and Clinical Center, San Francisco Veterans Affairs Medical Center, San Francisco, California, USA.
authors.forename: Jill L
authors.initials: JL
authors.lastname: Ostrem
mesh_terms: D000368:Aged; D001288:Attention; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology; D046690:Deep Brain Stimulation / Q000379:methods*; D004421:Dystonia / Q000523:psychology* / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D009483:Neuropsychological Tests; D011446:Prospective Studies; D011597:Psychomotor Performance; D020531:Subthalamic Nucleus
keywords: Cognition; Dystonia; Memory