National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan.
Department of Psychological Science, Kwansei Gakuin University, Nishinomiya, Japan.
Neuropsychologia. 2018 Oct;119:271-279. doi: 10.1016/j.neuropsychologia.2018.08.031. Epub 2018 Sep 3.
The present study aimed to investigate whether coincidence of opinion affects the evaluative processing of outcomes in group decision-making under authority rule. For this purpose, we examined the effects of the opinion coincidence on feedback-related negativity (FRN), an event-related brain potential (ERP) reflecting the evaluative processing of outcomes. Six three-person groups performed a group decision-making task in which one member acting as a leader (leader blocks) made a group decision to choose one of two cards after he/she observed opinions of the other members acting as followers (follower blocks), and monetary gain or loss was contingent on the group decision. To examine the effect of the opinion coincidence, each trial of each individual was classified into one of three trial types: unanimous, majority, or minority trials. As a result, the amplitude of FRN was smaller for unanimous trials than for majority trials in the leader blocks. In addition, the amplitude of FRN was larger for majority trials compared to minority trials in the follower blocks. These results suggest that the coincidence of opinion in group decision-making affects the evaluative processing of outcomes, and this occurs even when roles and responsibilities over outcomes is explicitly clarified under the authority rule.
本研究旨在探讨意见一致是否会影响权威规则下群体决策中结果的评价加工。为此，我们考察了意见一致对反馈相关负波（FRN）的影响，FRN 是一种反映结果评价加工的事件相关脑电位（ERP）。六组三人小组进行了一项群体决策任务，其中一名成员作为领导者（领导者组）在观察其他两名作为追随者的成员的意见后，对两张卡片中的一张做出群体决策，并且群体决策决定了金钱的收益或损失。为了考察意见一致的影响，每个个体的每个试次被分为三种试次类型之一：一致、多数和少数试次。结果表明，在领导者组中，一致试次的 FRN 振幅小于多数试次；在追随者组中，多数试次的 FRN 振幅大于少数试次。这些结果表明，群体决策中的意见一致会影响结果的评价加工，即使在权威规则下明确规定了角色和对结果的责任。
