title: Impaired visual perception in rapid eye movement sleep behavior disorder.
abstract: OBJECTIVE
  Patients with idiopathic REM sleep behavior disorder (iRBD) often develop synucleinopathies (Parkinson's disease [PD], in particular). Cognitive disorders affecting different domains have been reported in patients with iRBD. Dysexecutive disorders seem to predominate, but there is no consensus on the nature of visuospatial disorders in iRBD. The objective is to identify and characterize visuospatial disorders in patients with REM sleep behavior disorder (RBD - either idiopathic or associated with PD).
  
  
  METHODS
  Fifteen patients with iRBD, 30 patients with PD (15 of whom had RBD), and 20 healthy control subjects underwent an extensive assessment of visuospatial functions. Two computerized tasks were used: a Biederman task (to assess the 3 levels of visuoperceptive processing) and a Posner paradigm (to assess visual attention).
  
  
  RESULTS
  The visual priming effects classically described for the Biederman task in healthy controls were not found in iRBD patients. Patients with iRBD were no quicker in naming objects with the same general structure as previously presented objects but did have a normal priming effect for strictly identical objects. Parkinson's disease patients with RBD had poorer visuoperceptive performance levels than PD patients without RBD. There were no significant differences between the 4 groups in the Posner attentional task.
  
  
  CONCLUSIONS
  First, this study confirms the presence of visuoperceptive dysfunction in iRBD patients and revealed a selective defect in intermediate visuoperceptive processing (i.e., general object representation). Second, RBD in PD appeared to be associated with poorer visuoperceptive abilities. Third, this visuoperceptive dysfunction in RBD patients was not associated with impaired attention.
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Lucie
authors.initials: L
authors.lastname: Plomhause
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Kathy
authors.initials: K
authors.lastname: Dujardin
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Muriel
authors.initials: M
authors.lastname: Boucart
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Virginie
authors.initials: V
authors.lastname: Herlin
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Luc
authors.initials: L
authors.lastname: Defebvre
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Philippe
authors.initials: P
authors.lastname: Derambure
authors.affiliation: EA 4559, Lille Nord de France University.
authors.forename: Christelle
authors.initials: C
authors.lastname: Monaca Charley
mesh_terms: D000368:Aged; D001288:Attention; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications; D010468:Perceptual Disorders / Q000175:diagnosis / Q000209:etiology*; D010775:Photic Stimulation; D017286:Polysomnography; D020187:REM Sleep Behavior Disorder / Q000150:complications*; D014796:Visual Perception