PDF(Pubmed)
Abstract：
The mini-Ultimatum Game (mini-UG) is a bargaining game used to assess the reactions of a responder to unfair offers made by a proposer under different intentionality conditions. Previous studies employing this task showed the activation of responders\' right temporoparietal junction (rTPJ), which could be related to its involvement in judgments of intentionality. To verify this hypothesis, in the present study we applied online transcranial magnetic stimulation (TMS) over the rTPJ in responders during the mini-UG, in which we manipulated intention attribution implicitly. A cover story was employed to induce participants to believe they were interacting with another agent. We expected that interfering with the rTPJ could affect the ability of responders to assume proposers\' perspective, producing higher rates of rejections of unfair offers when offers are perceived as independent from responders\' intentionality to inequality. Twenty-six healthy women voluntarily participated in the study. In the mini-UG, an unfair distribution of the proposer (8/2 offer) was pitted against one of three alternative offers: fair-alternative (5/5), no-alternative (8/2), hyperfair-alternative (2/8). During the task, a train of TMS pulses was delivered at proposers\' offer presentation in blocks of active (rTPJ) or control (Vertex) stimulation according to an ABAB design. As expected, findings showed that rejection of the no-alternative offers was higher under TMS stimulation of the rTPJ compared with the control TMS. This effect was modulated by the degree of trustworthiness in the cover story. These data contribute defining the mechanisms and brain areas underpinning social decision making as assessed by bargaining tasks.
摘要：
迷你最后通牒游戏（mini-UG）是一种讨价还价游戏，用于评估响应者在不同的故意条件下对提案人提出的不公平报价的反应。以前使用这项任务的研究表明，应答者右颞顶交界处(rTPJ)的激活，这可能与它参与故意判断有关。为了验证这个假设，在本研究中，我们将在线经颅磁刺激（TMS）应用于微型UG期间的应答者rTPJ，其中我们隐含地操纵了意图归因。封面故事被用来诱使参与者相信他们正在与另一个代理人互动。我们预计干扰rTPJ可能会影响响应者承担提案者观点的能力，当报价被认为是独立于响应者的故意不平等时，产生更高的不公平报价拒绝率。26名健康女性自愿参加了这项研究。在迷你UG中，提案人的不公平分配(8/2报价)与三个替代报价之一:公平替代(5/5)，无替代(8/2)，hyperfair-替代（2/8）。任务期间,根据ABAB设计,以主动(rTPJ)或对照(顶点)刺激块的形式,在提交者提供一系列TMS脉冲。不出所料,研究结果表明，与对照TMS相比，在rTPJ的TMS刺激下，对无替代选择的拒绝更高。这种效果是由封面故事中的可信度调节的。这些数据有助于确定讨价还价任务所评估的支撑社会决策的机制和大脑区域。
