a Social and Cognitive Neuroscience Laboratory and Developmental Disorders Program , Center for Health and Biological Sciences, Mackenzie Presbyterian University , São Paulo , Brazil.
Soc Neurosci. 2017 Oct;12(5):530-540. doi: 10.1080/17470919.2016.1195772. Epub 2016 Jun 13.
The ultimatum game (UG) is an endowment sharing game in which a proposer suggests a division of an asset to a recipient, who must accept or reject it. Economic studies showed that despite recipients usually rejecting unfair offers, perception and reaction to unfairness are highly dependent on who is the proposer. Event-related potentials (ERPs) commonly detected in UG games are the medial frontal negativity (MFN), a component detected in recipients facing unfair offers, and the P300, a component related to attentional and memory processes. Given this, we aimed to investigate the behavioral and ERP responses of healthy people playing the UG game with Down syndrome (DS) and typical development (TD) proposers. Nineteen subjects participated in this study. The UG behavioral data were similar to previous studies. ERP analysis showed no MFN in participants facing unfair offers. A higher P300 amplitude was detected when participants faced fair offers from TD compared to DS fair offers. We also found a positive correlation between P300 amplitude for TD offers and self-esteem scale score. Together these findings indicate that insertion of an atypical player in the UG led to changes in participants' perception and expectancy of the game.
最后通牒游戏（UG）是一种资产分配游戏，其中提议者向接受者建议分配资产，接受者必须接受或拒绝。经济研究表明，尽管接受者通常会拒绝不公平的提议，但对不公平的感知和反应高度取决于谁是提议者。在 UG 游戏中通常检测到的事件相关电位（ERP）包括中额负波（MFN），这是接受不公平提议的接受者检测到的一个成分，以及 P300，这是与注意力和记忆过程相关的一个成分。有鉴于此，我们旨在研究与唐氏综合征（DS）和典型发育（TD）提议者一起玩 UG 游戏的健康人的行为和 ERP 反应。19 名受试者参加了这项研究。UG 的行为数据与先前的研究相似。ERP 分析显示，参与者面对不公平的提议时没有 MFN。参与者面对 TD 的公平提议时，P300 振幅更高，而面对 DS 的公平提议时则较低。我们还发现，TD 提议的 P300 振幅与自尊量表评分呈正相关。这些发现表明，在 UG 中插入一个非典型的参与者会导致参与者对游戏的感知和期望发生变化。
