title: Unexpected downshifts in reward magnitude induce variation in human behavior.
abstract: We investigated how changes in outcome magnitude affect behavioral variation in human volunteers. Our participants entered strings of characters using a computer keyboard, receiving feedback (gaining a number of points) for any string at least ten characters long. During a "surprise" phase in which the number of points awarded was changed, participants only increased their behavioral variability when the reward value was downshifted to a lower amount, and only when such a shift was novel. Upshifts in reward did not have a systematic effect on variability.
authors.affiliation: Columbia University, New York City, NY, USA, greg.guichard.jensen@gmail.com.
authors.forename: Greg
authors.initials: G
authors.lastname: Jensen
authors.forename: Patricia D
authors.initials: PD
authors.lastname: Stokes
authors.forename: Anthea
authors.initials: A
authors.lastname: Paterniti
authors.forename: Peter D
authors.initials: PD
authors.lastname: Balsam
mesh_terms: D000328:Adult; D030141:Feedback, Psychological / Q000502:physiology*; D005260:Female; D006801:Humans; D011597:Psychomotor Performance / Q000502:physiology*; D012201:Reward; D055815:Young Adult