title: Spatial learning deficits in Parkinson's disease with and without mild cognitive impairment.
abstract: Several MRI studies have demonstrated hippocampal atrophy in Parkinson's disease (PD), a structure considered a key element in spatial learning. Despite this, no study has been undertaken to investigate spatial navigation in PD using a virtual version of the Morris water maze, which is the gold standard for testing hippocampal function in rodents.
  
  
  
  We studied 17 cognitively unimpaired PD patients, 12 PD patients with mild cognitive impairment (MCI) and 15 controls in a virtual water maze procedure.
  
  
  
  Measured by the main outcome parameters latency to locate the target and heading error (average difference between direction of movement toward anticipated target and real direction toward the target), controls performed significantly better on the virtual water maze task than cognitively unimpaired PD patients or PD patients with MCI, while there was no significant difference between latter two groups.
  
  
  
  The virtual water maze test differentiates PD patients from controls, but does not distinguish between cognitively normal and cognitively impaired PD patients, indicating a possible dopamine dependent component in spatial learning. Spatial performance deficits might thus constitute very early signs of dopamine depletion independent of the presence of MCI in Parkinson's disease.
authors.affiliation: Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany. Electronic address: Christine.Schneider@uniklinikum-dresden.de.
authors.forename: Christine B
authors.initials: CB
authors.lastname: Schneider
authors.affiliation: Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Linse
authors.affiliation: Institute of Psychology, Division of Clinical Psychology, Martin-Luther-University Halle-Wittenberg, 06099 Halle (Saale), Germany.
authors.forename: Robby
authors.initials: R
authors.lastname: Schönfeld
authors.affiliation: Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brown
authors.affiliation: Department of Medical Informatics and Biometry, Technische Universität Dresden, 01307 Dresden, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Koch
authors.affiliation: Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Reichmann
authors.affiliation: Institute of Psychology, Division of Clinical Psychology, Martin-Luther-University Halle-Wittenberg, 06099 Halle (Saale), Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Leplow
authors.affiliation: Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany; Department of Neurology, University of Rostock, 18147 Rostock, Germany; German Centre for Neurodegenerative Diseases (DZNE), 18147 Rostock, Germany. Electronic address: Alexander.Storch@med.uni-rostock.de.
authors.forename: Alexander
authors.initials: A
authors.lastname: Storch
mesh_terms: D000368:Aged; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000523:psychology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000523:psychology*; D065853:Spatial Learning / Q000502:physiology*; D000076142:Virtual Reality
keywords: Cognition; Mild cognitive impairment; Parkinson's disease; Spatial navigation; Virtual water maze