Unexpected downshifts in reward magnitude induce variation in human behavior
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.
KeywordsHuman learning Variability
The authors thank Karen Zechowy and Jacqui Rick for their assistance in conducting this experiment. This work was supported by National Institute of Mental Health Grant No. 5R01MH068073, awarded to P.B.
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