title: Aversion learning can reduce meal size without taste avoidance in rats.
abstract: OBJECTIVE
  Nausea and aversive food responses are commonly reported following bariatric surgery, along with post-surgical reduction in meal size. This study investigates whether a meal size limit can be conditioned by associating large meals with aversive outcomes.
  
  
  METHODS
  In rats, the intake of meals exceeding a pre-defined size threshold was paired with lithium chloride-induced gastric illness, and the effects on self-determined food intakes and body weight were measured.
  
  
  RESULTS
  Rats given LiCl contingent on the intake of a large meal learned to reliably reduce intake below this meal size threshold, while post-meal saline or LiCl before meals did not change meal size. It was further demonstrated that this is not a conditioned taste aversion and that this effect transferred to foods not explicitly trained. Finally, when rats received LiCl following all large meals, the number of small meals increased, but total food intake and body weight decreased.
  
  
  CONCLUSIONS
  While further work is needed, this is the first demonstration that meal size may be conditioned, using an aversion procedure, to remain under a target threshold and that this effect is distinct from taste avoidance. Corresponding reduction in food intake and body weight suggests that this phenomenon may have implications for developing weight loss strategies and understanding the efficacy of bariatric surgery.
authors.affiliation: Department of Psychology, Grinnell College, Grinnell, Iowa, USA.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Tracy
authors.affiliation: Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Jennifer D
authors.initials: JD
authors.lastname: Schurdak
authors.affiliation: Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: James B
authors.initials: JB
authors.lastname: Chambers
authors.affiliation: Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Benoit
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000633:toxicity*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D004435:Eating / Q000187:drug effects*; D018021:Lithium Chloride / Q000008:administration & dosage* / Q000633:toxicity; D051381:Rats; D013649:Taste / Q000187:drug effects*
chemical_list: D000276:Adjuvants, Immunologic; D018021:Lithium Chloride