title: Reward circuitry responsivity to food predicts future increases in body mass: moderating effects of DRD2 and DRD4.
abstract: OBJECTIVE
  To determine whether responsivity of reward circuitry to food predicts future increases in body mass and whether polymorphisms in DRD2 and DRD4 moderate these relations.
  
  
  METHODS
  The functional magnetic resonance imaging (fMRI) paradigm investigated blood oxygen level dependent activation in response to imagined intake of palatable foods, unpalatable foods, and glasses of water shown in pictures. DNA was extracted from saliva samples using standard salting-out and solvent precipitation methods.
  
  
  METHODS
  Forty-four adolescent female high school students ranging from lean to obese.
  
  
  RESULTS
  Future increases in body mass index (BMI).
  
  
  RESULTS
  Weaker activation of the frontal operculum, lateral orbitofrontal cortex, and striatum in response to imagined intake of palatable foods, versus imagined intake of unpalatable foods or water, predicted future increases in body mass for those with the DRD2 TaqIA A1 allele or the DRD4-7R allele. Data also suggest that for those lacking these alleles, greater responsivity of these food reward regions predicted future increases in body mass.
  
  
  CONCLUSIONS
  This novel prospective fMRI study indicates that responsivity of reward circuitry to food increases risk for future weight gain, but that genes that impact dopamine signaling capacity moderate the predictive effects, suggesting two qualitatively distinct pathways to unhealthy weight gain based on genetic risk.
authors.affiliation: Oregon Research Institute, 1715 Franklin Blvd., Eugene, OR 97403, USA. estice@ori.org
authors.forename: Eric
authors.initials: E
authors.lastname: Stice
authors.forename: Sonja
authors.initials: S
authors.lastname: Yokum
authors.forename: Cara
authors.initials: C
authors.lastname: Bohon
authors.forename: Nate
authors.initials: N
authors.lastname: Marti
authors.forename: Andrew
authors.initials: A
authors.lastname: Smolen
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D004326:Drinking / Q000502:physiology; D004435:Eating / Q000502:physiology*; D005260:Female; D005502:Food; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D009434:Neural Pathways / Q000098:blood supply / Q000502:physiology; D009765:Obesity / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D010100:Oxygen / Q000097:blood; D011110:Polymorphism, Genetic; D011446:Prospective Studies; D050637:Receptors, Dopamine D3 / Q000235:genetics* / Q000378:metabolism; D050638:Receptors, Dopamine D4 / Q000235:genetics* / Q000378:metabolism; D012201:Reward; D012463:Saliva / Q000737:chemistry / Q000378:metabolism; D014867:Water; D015430:Weight Gain / Q000235:genetics* / Q000502:physiology*
chemical_list: C493599:DRD4 protein, human; D050637:Receptors, Dopamine D3; D014867:Water; D050638:Receptors, Dopamine D4; D010100:Oxygen