title: Decision making and executive functions in REM sleep behavior disorder.
abstract: OBJECTIVE
  This study was designed to assess decision making and executive functions in patients with idiopathic REM sleep behavior disorder (iRBD). IRBD is often seen as an early sign of later evolving neurodegenerative disease, most importantly Parkinson disease (PD) and Lewy body dementia (DLB). It has been proposed that iRBD patients show a cognitive profile similar to patients with PD.
  
  
  METHODS
  All participants performed an extensive test battery tapping executive functions as well as the IOWA gambling task, which measures decision making under ambiguity.
  
  
  METHODS
  University hospital sleep disorders center.
  
  
  METHODS
  16 iRBD patients and 45 age- and education-matched controls.
  
  
  METHODS
  N.A.
  
  
  RESULTS
  Compared with controls, iRBD patients showed disadvantageous decision making under ambiguity and did not learn by feedback over the task. IRBD patients' decision pattern was characterized by the lack of a consistent strategy, as indicated by frequent shifts between the single choices. A high proportion of iRBD patients (75%) showed random performance or worse even at the end of the task. No group differences were found in tasks assessing information sampling, flexibility and categorization, problem solving, and impulsivity.
  
  
  CONCLUSIONS
  As suggested by the present investigation, iRBD patients may show difficulties in decision making under ambiguity in a stage when other cognitive functions are relatively well preserved. Whether this is driven by subgroups of patients prone to develop PD or DLB has to be assessed by follow-up investigations.
authors.affiliation: Department of Neurology, Innsbruck, Medical University, Innsbruck, Austria.
authors.forename: Margarete
authors.initials: M
authors.lastname: Delazer
authors.forename: Birgit
authors.initials: B
authors.lastname: Högl
authors.forename: Laura
authors.initials: L
authors.lastname: Zamarian
authors.forename: Johanna
authors.initials: J
authors.lastname: Wenter
authors.forename: Laura
authors.initials: L
authors.lastname: Ehrmann
authors.forename: Viola
authors.initials: V
authors.lastname: Gschliesser
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Brandauer
authors.forename: Werner
authors.initials: W
authors.lastname: Poewe
authors.forename: Birgit
authors.initials: B
authors.lastname: Frauscher
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D003657:Decision Making; D056344:Executive Function; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D020187:REM Sleep Behavior Disorder / Q000523:psychology*