title: Eye Movement in Unipolar and Bipolar Depression: A Systematic Review of the Literature.
abstract: BACKGROUND
  The analysis of eye movements (EM) by eye-tracking has been carried out for several decades to investigate mood regulation, emotional information processing, and psychomotor disturbances in depressive disorders.
  
  
  METHODS
  A systematic review of all English language PubMed articles using the terms "saccadic eye movements" OR "eye-tracking" AND "depression" OR "bipolar disorders" was conducted using PRISMA guidelines. The aim of this review was to characterize the specific alterations of EM in unipolar and bipolar depression.
  
  
  RESULTS
  Findings regarding psychomotor disturbance showed an increase in reaction time in prosaccade and antisaccade tasks in both unipolar and bipolar disorders. In both disorders, patients have been reported to have an attraction for negative emotions, especially for negative pictures in unipolar and threatening images in bipolar disorder. However, the pattern could change with aging, elderly unipolar patients disengaging key features of sad and neutral stimuli. METHODological limitations generally include small sample sizes with mixed unipolar and bipolar depressed patients.
  
  
  CONCLUSIONS
  Eye movement analysis can be used to discriminate patients with depressive disorders from controls, as well as patients with bipolar disorder from patients with unipolar depression. General knowledge concerning psychomotor alterations and affective regulation strategies associated with each disorder can also be gained thanks to the analysis. Future directions for research on eye movement and depression are proposed in this review.
authors.affiliation: Department of Clinical Psychiatry, University of Bourgogne Franche-Comté, University Hospital Besançon, France ; E.A. 481, Laboratory of Neurosciences, University of Franche-Comté Besançon, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Carvalho
authors.affiliation: E.A. 3188, Laboratory of Psychology, University of Franche-Comté Besançon, France ; UMSR 3124/FED 4209 MSHE Ledoux, Centre National de la Recherche Scientifique/Université de Franche-Comté Besançon, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Laurent
authors.affiliation: Department of Clinical Psychiatry, University of Bourgogne Franche-Comté, University Hospital Besançon, France ; E.A. 3188, Laboratory of Psychology, University of Franche-Comté Besançon, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Noiret
authors.affiliation: Department of Clinical Psychiatry, University of Bourgogne Franche-Comté, University Hospital Besançon, France ; E.A. 481, Laboratory of Neurosciences, University of Franche-Comté Besançon, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Chopard
authors.affiliation: Department of Clinical Psychiatry, University of Bourgogne Franche-Comté, University Hospital Besançon, France ; E.A. 481, Laboratory of Neurosciences, University of Franche-Comté Besançon, France ; Fondation FondaMental, Albert Chenevier Hospital Créteil, France ; CIC-IT 808 Inserm, Besançon University Hospital Besançon, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Haffen
authors.affiliation: Department of Clinical Psychiatry, University of Bourgogne Franche-Comté, University Hospital Besançon, France ; E.A. 481, Laboratory of Neurosciences, University of Franche-Comté Besançon, France.
authors.forename: Djamila
authors.initials: D
authors.lastname: Bennabi
authors.affiliation: Department of Clinical Psychiatry, University of Bourgogne Franche-Comté, University Hospital Besançon, France ; E.A. 481, Laboratory of Neurosciences, University of Franche-Comté Besançon, France ; CIC-IT 808 Inserm, Besançon University Hospital Besançon, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Vandel
keywords: bipolar depression; emotion; eye movement; saccade; unipolar depression