title: Predictive pursuit association with deficits in working memory in psychosis.
abstract: BACKGROUND
  Deficits in smooth pursuit eye movements are an established phenotype for schizophrenia (SZ) and are being investigated as a potential liability marker for bipolar disorder. Although the molecular determinants of this deficit are still unclear, research has verified deficits in predictive pursuit mechanisms in SZ. Because predictive pursuit might depend on the working memory system, we have hypothesized a relationship between the two in healthy control subjects (HC) and SZ and here examine whether it extends to psychotic bipolar disorder (BDP).
  
  
  METHODS
  Volunteers with SZ (n = 38), BDP (n = 31), and HC (n = 32) performed a novel eye movement task to assess predictive pursuit as well as a standard visuospatial measure of working memory.
  
  
  RESULTS
  Individuals with SZ and BDP both showed reduced predictive pursuit gain compared with HC (p < .05). Moreover, each patient group showed worse performance in visuospatial working memory compared with control subjects (p < .05). A strong correlation (r = .53, p = .007) was found between predictive pursuit gain and working memory in HC, a relationship that showed a trend correlation within the BDP group but not among SZ.
  
  
  CONCLUSIONS
  Individuals with SZ and BDP showed similar deficits in predictive pursuit, suggesting that this alteration could be a characteristic trait of the psychosis domain. The correlation between predictive pursuit and working memory in HC supports the assumption that working memory is related to predictive pursuit eye movements; however, the degradation of working memory in people with psychosis disrupts its association with eye-tracking behavior.
authors.affiliation: Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas, USA. Amanda.Moates@UTSouthwestern.edu
authors.forename: Amanda F
authors.initials: AF
authors.lastname: Moates
authors.forename: Elena I
authors.initials: EI
authors.lastname: Ivleva
authors.forename: Hugh B
authors.initials: HB
authors.lastname: O'Neill
authors.forename: Nithin
authors.initials: N
authors.lastname: Krishna
authors.forename: C Munro
authors.initials: CM
authors.lastname: Cullum
authors.forename: Gunvant K
authors.initials: GK
authors.lastname: Thaker
authors.forename: Carol A
authors.initials: CA
authors.lastname: Tamminga
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000150:complications / Q000503:physiopathology / Q000523:psychology*; D016022:Case-Control Studies; D005133:Eye Movements / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000150:complications / Q000503:physiopathology / Q000523:psychology*; D008570:Memory, Short-Term / Q000502:physiology*; D015835:Ocular Motility Disorders / Q000150:complications / Q000503:physiopathology / Q000523:psychology*; D011597:Psychomotor Performance / Q000502:physiology; D012559:Schizophrenia / Q000150:complications / Q000503:physiopathology; D012565:Schizophrenic Psychology