title: Impulsivity in disorders of food and drug misuse.
abstract: BACKGROUND
  Evidence suggests some overlap between the pathological use of food and drugs, yet how impulsivity compares across these different clinical disorders remains unclear. Substance use disorders are commonly characterized by elevated impulsivity, and impulsivity subtypes may show commonalities and differences in various conditions. We hypothesized that obese subjects with binge-eating disorder (BED) and abstinent alcohol-dependent cohorts would have relatively more impulsive profiles compared to obese subjects without BED. We also predicted decision impulsivity impairment in obesity with and without BED.
  
  
  METHODS
  Thirty obese subjects with BED, 30 without BED and 30 abstinent alcohol-dependent subjects and age- and gender-matched controls were tested on delay discounting (preference for a smaller immediate reward over a larger delayed reward), reflection impulsivity (rapid decision making prior to evidence accumulation) and motor response inhibition (action cancellation of a prepotent response).
  
  
  RESULTS
  All three groups had greater delay discounting relative to healthy volunteers. Both obese subjects without BED and alcohol-dependent subjects had impaired motor response inhibition. Only obese subjects without BED had impaired integration of available information to optimize outcomes over later trials with a cost condition.
  
  
  CONCLUSIONS
  Delay discounting appears to be a common core impairment across disorders of food and drug intake. Unexpectedly, obese subjects without BED showed greater impulsivity than obese subjects with BED. We highlight the dissociability and heterogeneity of impulsivity subtypes and add to the understanding of neurocognitive profiles across disorders involving food and drugs. Our results have therapeutic implications suggesting that disorder-specific patterns of impulsivity could be targeted.
authors.affiliation: Department of Psychiatry,University of Cambridge,Cambridge,UK.
authors.forename: T B
authors.initials: TB
authors.lastname: Mole
authors.affiliation: Department of Psychiatry,University of Cambridge,Cambridge,UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Irvine
authors.affiliation: Behavioural and Clinical Neuroscience Institute,University of Cambridge,Cambridge,UK.
authors.forename: Y
authors.initials: Y
authors.lastname: Worbe
authors.affiliation: Department of Psychiatry,University of Cambridge,Cambridge,UK.
authors.forename: P
authors.initials: P
authors.lastname: Collins
authors.affiliation: Department of Psychiatry,University of Cambridge,Cambridge,UK.
authors.forename: S P
authors.initials: SP
authors.lastname: Mitchell
authors.affiliation: Department of Psychiatry,University of Cambridge,Cambridge,UK.
authors.forename: S
authors.initials: S
authors.lastname: Bolton
authors.affiliation: Brighton and Sussex Medical School,University of Sussex,Brighton,UK.
authors.forename: N A
authors.initials: NA
authors.lastname: Harrison
authors.affiliation: Behavioural and Clinical Neuroscience Institute,University of Cambridge,Cambridge,UK.
authors.forename: T W
authors.initials: TW
authors.lastname: Robbins
authors.affiliation: Department of Psychiatry,University of Cambridge,Cambridge,UK.
authors.forename: V
authors.initials: V
authors.lastname: Voon
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000503:physiopathology*; D056912:Binge-Eating Disorder / Q000503:physiopathology*; D065786:Delay Discounting / Q000502:physiology*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000502:physiology*; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*
keywords: stop signal task