title: Vision, visuo-cognition and postural control in Parkinson's disease: An associative pilot study.
abstract: Impaired postural control (PC) is common in patients with Parkinson's disease (PD) and is a major contributor to falls, with significant consequences. Mechanisms underpinning PC are complex and include motor and non-motor features. Research has focused predominantly on motor and sensory inputs. Vision and visuo-cognitive function are also integral to PC but have largely been ignored to date. The aim of this observational cross-sectional pilot study was to explore the relationship of vision and visuo-cognition with PC in PD.
  
  
  
  Twelve people with PD and ten age-matched healthy controls (HC) underwent detailed assessments for vision, visuo-cognition and postural control. Vision assessments included visual acuity and contrast sensitivity. Visuo-cognition was measured by visuo-perception (object identification), visuo-construction (ability to copy a figure) and visuo-spatial ability (judge distances and location of object within environment). PC was measured by an accelerometer for a range of outcomes during a 2-min static stance. Spearman's correlations identified significant associations.
  
  
  
  Contrast sensitivity, visuo-spatial ability and postural control (ellipsis) were significantly impaired in PD (p=0.017; p=0.001; and p=0.017, respectively). For PD only, significant correlations were found for higher visuo-spatial function and larger ellipsis (r=0.64; p=0.024) and impaired attention and reduced visuo-spatial function (r=-0.62; p=0.028).
  
  
  
  Visuo-spatial ability is associated with PC deficit in PD, but in an unexpected direction. This suggests a non-linear pattern of response. Further research is required to examine this novel and important finding.
authors.affiliation: Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Newcastle University, United Kingdom.
authors.forename: E
authors.initials: E
authors.lastname: Hill
authors.affiliation: Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Newcastle University, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Stuart
authors.affiliation: Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Newcastle University, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Lord
authors.affiliation: Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Newcastle University, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Del Din
authors.affiliation: Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Newcastle University, United Kingdom. Electronic address: lynn.rochester@newcastle.ac.uk.
authors.forename: L
authors.initials: L
authors.lastname: Rochester
mesh_terms: D000368:Aged; D001288:Attention / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology*; D010865:Pilot Projects; D011434:Proprioception / Q000502:physiology*; D065854:Spatial Navigation / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*
keywords: Cognition; Parkinson's disease; Postural control; Vision; Visuo-cognition