Xu Eric R, Knight Emily J, Kralik Jerald D
Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH 03755, USA.
Q J Exp Psychol (Hove). 2011 Dec;64(12):2301-15. doi: 10.1080/17470218.2011.591936. Epub 2011 Sep 20.
In humans, the order of receiving sequential rewards can significantly influence the overall subjective utility of an outcome. For example, people subjectively rate receiving a large reward by itself significantly higher than receiving the same large reward followed by a smaller one (Do, Rupert, & Wolford, 2008). This result is called the peak-end effect. A comparative analysis of order effects can help determine the generality of such effects across primates, and we therefore examined the influence of reward-quality order on decision making in three rhesus macaque monkeys (Macaca mulatta). When given the choice between a high-low reward sequence and a low-high sequence, all three monkeys preferred receiving the high-value reward first. Follow-up experiments showed that for two of the three monkeys their choices depended specifically on reward-quality order and could not be accounted for by delay discounting. These results provide evidence for the influence of outcome order on decision making in rhesus monkeys. Unlike humans, who usually discount choices when a low-value reward comes last, rhesus monkeys show no such peak-end effect.
在人类中，接受连续奖励的顺序会显著影响结果的整体主观效用。例如，人们主观上对单独获得一个大奖励的评价要远高于先获得一个大奖励后再获得一个小奖励的情况（Do、Rupert和Wolford，2008年）。这一结果被称为峰终效应。对顺序效应进行比较分析有助于确定此类效应在灵长类动物中的普遍性，因此我们研究了奖励质量顺序对三只恒河猴（猕猴）决策的影响。当在高低奖励序列和低高奖励序列之间进行选择时，所有三只猴子都更喜欢先获得高价值奖励。后续实验表明，三只猴子中有两只的选择具体取决于奖励质量顺序，而不能用延迟折扣来解释。这些结果为结果顺序对恒河猴决策的影响提供了证据。与人类不同，当低价值奖励排在最后时，人类通常会对选择进行折扣，而恒河猴则没有这种峰终效应。
