Impulsivity in binge eating disorder: food cues elicit increased reward responses and disinhibition

PLoS One. 2013 Oct 16;8(10):e76542. doi: 10.1371/journal.pone.0076542. eCollection 2013.

Abstract

Background: Binge eating disorder (BED) represents a distinct eating disorder diagnosis. Current approaches assume increased impulsivity to be one factor leading to binge eating and weight gain. We used eye tracking to investigate both components of impulsivity, namely reward sensitivity and rash-spontaneous behaviour towards food in BED for the first time.

Methods: Overweight and obese people with BED (BED+; n = 25), without BED (BED-; n = 26) and healthy normal-weight controls (NWC; n = 25) performed a free exploration paradigm measuring reward sensitivity (experiment 1) and a modified antisaccade paradigm measuring disinhibited, rash-spontaneous behaviour (experiment 2) using food and nonfood stimuli. Additionally, trait impulsivity was assessed.

Results: In experiment 1, all participants located their initial fixations more often on food stimuli and BED+ participants gazed longer on food stimuli in comparison with BED- and NWC participants. In experiment 2, BED+ participants had more difficulties inhibiting saccades towards food and nonfood stimuli compared with both other groups in first saccades, and especially towards food stimuli in second saccades and concerning sequences of first and second saccades. BED- participants did not differ significantly from NWC participants in both experiments. Additionally, eye tracking performance was associated with self-reported reward responsiveness and self-control.

Conclusions: According to these results, food-related reward sensitivity and rash-spontaneous behaviour, as the two components of impulsivity, are increased in BED in comparison with weight-matched and normal-weight controls. This indicates that BED represents a neurobehavioural phenotype of obesity that is characterised by increased impulsivity. Interventions for BED should target these special needs of affected patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Binge-Eating Disorder / complications*
  • Cues*
  • Female
  • Fixation, Ocular
  • Food*
  • Humans
  • Impulsive Behavior / complications*
  • Inhibition, Psychological*
  • Photic Stimulation
  • Reward*
  • Saccades / physiology

Grant support

The authors are grateful for funding support from a grant of the fortüne programme of the Medical Faculty Tübingen (project number F1292005) (URL: http://www.med.uni-tuebingen.de/Forschung/Forschung_F%C3%B6rderunganderMedizinischenFakult%C3%A4t/fort%C3%BCne.html). The authors acknowledge support by Deutsche Forschungsgemeinschaft and Open Access Publishing Fund of Tübingen University, (URL: http://www.uni-tuebingen.de/einrichtungen/universitaetsbibliothek/lernen-lehren-forschen/open-access-publikationsfonds.html.) The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.