title: Salivary alpha-amylase levels and rejection of unfair offers in the ultimatum game.
abstract: OBJECTIVE
  This study aimed to examine the role of emotions in rejection of unfair offers in an ultimatum game, which is of interest in neuroeconomics of fairness.
  
  
  METHODS
  Thirty-seven participants played a one-shot ultimatum game as responders and decided whether to accept or reject the unfair offers by the proposers. Salivary alpha-amylase (sAA) was assessed before and after the ultimatum game.
  
  
  RESULTS
  Forty-four percent of the participants rejected the unfair offers. While sAA levels of the participants who rejected the unfair offers increased between pre- and post-experiment, sAA levels of the participants who accepted the unfair offers remain unchanged.
  
  
  CONCLUSIONS
  Emotional stress response was observed when participants rejected the unfair offers. Our results indicated that rejection of the unfair offers is a reflection of emotional arousal associated with adrenergic activations.
authors.affiliation: Department of Behavioral Sciences, Hokkaido University, Sapporo, 060-0810, Japan. taikitakahashi@gmail.com
authors.forename: Haruto
authors.initials: H
authors.lastname: Takagishi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Fujii
authors.forename: Shinya
authors.initials: S
authors.lastname: Kameshima
authors.forename: Michiko
authors.initials: M
authors.lastname: Koizumi
authors.forename: Taiki
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D000293:Adolescent; D002755:Choice Behavior / Q000502:physiology; D003657:Decision Making / Q000502:physiology; D004644:Emotions / Q000502:physiology*; D005260:Female; D005717:Games, Experimental; D006801:Humans; D009483:Neuropsychological Tests; D012463:Saliva / Q000201:enzymology*; D055291:Salivary alpha-Amylases / Q000378:metabolism*; D055815:Young Adult
chemical_list: D055291:Salivary alpha-Amylases