title: Visual object recognition and attention in Parkinson's disease patients with visual hallucinations.
abstract: Visual hallucinations (VH) are common in Parkinson's disease (PD) and are hypothesized to be due to impaired visual perception and attention deficits. We investigated whether PD patients with VH showed attention deficits, a more specific impairment of higher order visual perception, or both. Forty-two volunteers participated in this study, including 14 PD patients with VH, 14 PD patients without VH and 14 healthy controls (HC), matched for age, gender, education level and for level of executive function. We created movies with images of animals, people, and objects dynamically appearing out of random noise. Time until recognition of the image was recorded. Sustained attention was tested using the Test of Attentional Performance. PD patients with VH recognized all images but were significantly slower in image recognition than both PD patients without VH and HC. PD patients with VH showed decreased sustained attention compared to PD patients without VH who again performed worse than HC. In conclusion, the recognition of objects is intact in PD patients with VH; however, these patients where significantly slower in image recognition than patients without VH and HC, which was not explained by executive dysfunction. Both image recognition speed and sustained attention decline in PD, in a more progressive way if VH start to occur.
authors: Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands. a.m.meppelink@neuro.umcg.nl
authors: Anne Marthe
authors: AM
authors: Meppelink
authors: Janneke
authors: J
authors: Koerts
authors: Maarten
authors: M
authors: Borg
authors: Klaus Leonard
authors: KL
authors: Leenders
authors: Teus
authors: T
authors: van Laar
mesh_terms: D000368:Aged; D001288:Attention / Q000502:physiology*; D016022:Case-Control Studies; D005260:Female; D006212:Hallucinations / Q000150:complications*; D006801:Humans; D007092:Imagination / Q000502:physiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods