title: Disturbances of visual motion perception in bipolar disorder.
abstract: OBJECTIVE
  While cognitive deficits have been well documented in patients with bipolar disorder, visual perception has been less well characterized. Such deficits appear in schizophrenia, which shares genetic risk factors with bipolar disorder, and may contribute to disturbances in visual cognition and learning.
  
  
  METHODS
  The present study investigated visual perception in bipolar disorder using psychophysical tests of contrast sensitivity, dot motion discrimination, and form discrimination. The relationship of these measures to mood state, medication status, and cognitive function was investigated. Sixty-one patients with type I bipolar disorder and 67 comparison subjects were tested.
  
  
  RESULTS
  Results indicated a deficit in dot motion trajectory discrimination in both euthymic and ill individuals with bipolar disorder, as well as a global deficit in moving grating contrast sensitivity. Ill individuals with bipolar disorder were impaired in psychomotor processing, but this finding was not related to visual processing performance.
  
  
  CONCLUSIONS
  These findings could be due to disturbances in specific visual pathways involved in the processing of motion properties, or to a more general deficit which impairs processing of temporally modulated stimuli.
authors.affiliation: Indiana University Health, Southern Indiana Physicians, Bloomington, IN, USA.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: O'Bryan
authors.forename: Colleen A
authors.initials: CA
authors.lastname: Brenner
authors.forename: William P
authors.initials: WP
authors.lastname: Hetrick
authors.forename: Brian F
authors.initials: BF
authors.lastname: O'Donnell
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001714:Bipolar Disorder / Q000150:complications*; D015350:Contrast Sensitivity; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology; D010468:Perceptual Disorders / Q000175:diagnosis / Q000209:etiology*; D010775:Photic Stimulation; D011601:Psychophysics; D013223:Statistics as Topic
keywords: bipolar disorder; magnocellular; motion; parvocellular; psychiatric disorders; temporal processing; vision