title: Attentional grasp in Parkinson disease.
abstract: BACKGROUND
  Patients with Parkinson disease (PD) have deficits in the neurotransmitter systems important for the normal allocation of attention. We sought to examine how the presence of PD influences the spatial allocation of reactive (bottom-up) and volitional (top-down) attention.
  
  
  METHODS
  To assess the spatial allocation of attention, we used the line bisection task. When assessing "bottom-up" attention, lateral blinking lights were or were not present during the time the PD and normal subjects were attempting to perform line bisections. In the top-down condition, these subjects were asked to name the color of the laterally presented light before bisecting lines.
  
  
  RESULTS
  In the bottom-up condition, when compared with control subjects, the participants with PD were not abnormally distracted, but in the top-down condition, imperative stimuli on the right side of the line seemed to influence the PD subjects' allocation of attention.
  
  
  CONCLUSIONS
  The results suggest that when voluntarily allocating attention rightward, PD patients have difficulty disengaging and/or reallocating their attention. This disengagement deficit might be related to the frontal-executive dysfunction associated with PD.
authors.affiliation: Department of Neurology, University of Florida College of Medicine, Gainesville, FL, USA. valeria.drago@neurology.ufl.edu
authors.forename: Valeria
authors.initials: V
authors.lastname: Drago
authors.forename: Paul S
authors.initials: PS
authors.lastname: Foster
authors.forename: Frank M
authors.initials: FM
authors.lastname: Skidmore
authors.forename: Benzi
authors.initials: B
authors.lastname: Kluger
authors.forename: Daniel
authors.initials: D
authors.lastname: Antoniello
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Heilman
mesh_terms: D000368:Aged; D001288:Attention; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000453:epidemiology; D008570:Memory, Short-Term; D010300:Parkinson Disease / Q000453:epidemiology / Q000503:physiopathology*; D013028:Space Perception; D014796:Visual Perception; D014836:Volition