title: Visual Perceptual Organization Ability in Autopsy-Verified Dementia with Lewy Bodies and Alzheimer's Disease.
abstract: Prominent impairment of visuospatial processing is a feature of dementia with Lewy bodies (DLB), and diagnosis of this impairment may help clinically distinguish DLB from Alzheimer's disease (AD). The current study compared autopsy-confirmed DLB and AD patients on the Hooper Visual Organization Test (VOT), a test that requires perceptual and mental reorganization of parts of an object into an identifiable whole. The VOT may be particularly sensitive to DLB since it involves integration of visual information processed in separate dorsal and ventral visual "streams".
  
  
  
  Demographically similar DLB (n=28), AD (n=115), and normal control (NC; n=85) participants were compared on the VOT and additional neuropsychological tests. Patient groups did not differ in dementia severity at time of VOT testing. High and Low AD-Braak stage DLB subgroups were compared to examine the influence of concomitant AD pathology on VOT performance.
  
  
  
  Both patient groups were impaired compared to NC participants. VOT scores of DLB patients were significantly lower than those of AD patients. The diagnostic sensitivity and specificity of the VOT for patients versus controls was good, but marginal for DLB versus AD. High-Braak and low-Braak DLB patients did not differ on the VOT, but High-Braak DLB performed worse than Low-Braak DLB on tests of episodic memory and language.
  
  
  
  Visual perceptual organization ability is more impaired in DLB than AD but not strongly diagnostic. The disproportionate severity of this visual perceptual deficit in DLB is not related to degree of concomitant AD pathology, which suggests that it might primarily reflect Lewy body pathology. (JINS, 2016, 22, 609-619).
authors.affiliation: 1Fondazione San Camillo Ospedale - IRCCS,Venice,Italy.
authors.forename: Micaela
authors.initials: M
authors.lastname: Mitolo
authors.affiliation: 2Department of Neurosciences,University of California San Diego,San Diego,California.
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Hamilton
authors.affiliation: 2Department of Neurosciences,University of California San Diego,San Diego,California.
authors.forename: Kelly M
authors.initials: KM
authors.lastname: Landy
authors.affiliation: 2Department of Neurosciences,University of California San Diego,San Diego,California.
authors.forename: Lawrence A
authors.initials: LA
authors.lastname: Hansen
authors.affiliation: 2Department of Neurosciences,University of California San Diego,San Diego,California.
authors.forename: Douglas
authors.initials: D
authors.lastname: Galasko
authors.affiliation: 6Department of Psychology,University of Padua,Padua,Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Pazzaglia
authors.affiliation: 2Department of Neurosciences,University of California San Diego,San Diego,California.
authors.forename: David P
authors.initials: DP
authors.lastname: Salmon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000503:physiopathology*; D001344:Autopsy; D006801:Humans; D020961:Lewy Body Disease / Q000175:diagnosis / Q000503:physiopathology*; D009483:Neuropsychological Tests / Q000592:standards*; D014796:Visual Perception / Q000502:physiology*
keywords: Alzheimer’s disease; Dementia; Dementia with Lewy Bodies; Visual organization; Visuoperceptual deficit; Visuospatial deficit