title: Obese adults have visual attention bias for food cue images: evidence for altered reward system function.
abstract: BACKGROUND
  The major aim of this study was to investigate whether the motivational salience of food cues (as reflected by their attention-grabbing properties) differs between obese and normal-weight subjects in a manner consistent with altered reward system function in obesity.
  
  
  RESULTS
  A total of 18 obese and 18 normal-weight, otherwise healthy, adult women between the ages of 18 and 35 participated in an eye-tracking paradigm in combination with a visual probe task. Eye movements and reaction time to food and non-food images were recorded during both fasted and fed conditions in a counterbalanced design. Eating behavior and hunger level were assessed by self-report measures. Obese individuals had higher scores than normal-weight individuals on self-report measures of responsiveness to external food cues and vulnerability to disruptions in control of eating behavior. Both obese and normal-weight individuals demonstrated increased gaze duration for food compared to non-food images in the fasted condition. In the fed condition, however, despite reduced hunger in both groups, obese individuals maintained the increased attention to food images, whereas normal-weight individuals had similar gaze duration for food and non-food images. Additionally, obese individuals had preferential orienting toward food images at the onset of each image. Obese and normal-weight individuals did not differ in reaction time measures in the fasted or fed condition.
  
  
  CONCLUSIONS
  Food cue incentive salience is elevated equally in normal-weight and obese individuals during fasting. Obese individuals retain incentive salience for food cues despite feeding and decreased self-report of hunger. Sensitization to food cues in the environment and their dysregulation in obese individuals may play a role in the development and/or maintenance of obesity.
authors.affiliation: Psychiatric Neuroimaging Program, Vanderbilt University School of Medicine, Nashville, TN 37212, USA.
authors.forename: E H
authors.initials: EH
authors.lastname: Castellanos
authors.forename: E
authors.initials: E
authors.lastname: Charboneau
authors.forename: M S
authors.initials: MS
authors.lastname: Dietrich
authors.forename: S
authors.initials: S
authors.lastname: Park
authors.forename: B P
authors.initials: BP
authors.lastname: Bradley
authors.forename: K
authors.initials: K
authors.lastname: Mogg
authors.forename: R L
authors.initials: RL
authors.lastname: Cowan
mesh_terms: D000293:Adolescent; D000328:Adult; D003463:Cues; D005071:Evoked Potentials / Q000502:physiology; D005215:Fasting / Q000523:psychology; D005247:Feeding Behavior / Q000502:physiology / Q000523:psychology*; D005260:Female; D005502:Food; D006801:Humans; D006815:Hunger / Q000502:physiology*; D009765:Obesity / Q000503:physiopathology / Q000523:psychology*; D012201:Reward; D011795:Surveys and Questionnaires; D055815:Young Adult