Brain Science Institute, Tamagawa University, Machida, Tokyo 194-8610, Japan.
Proc Natl Acad Sci U S A. 2010 Dec 21;107(51):22014-9. doi: 10.1073/pnas.1011879108. Epub 2010 Dec 6.
According to many modern economic theories, actions simply reflect an individual's preferences, whereas a psychological phenomenon called "cognitive dissonance" claims that actions can also create preference. Cognitive dissonance theory states that after making a difficult choice between two equally preferred items, the act of rejecting a favorite item induces an uncomfortable feeling (cognitive dissonance), which in turn motivates individuals to change their preferences to match their prior decision (i.e., reducing preference for rejected items). Recently, however, Chen and Risen [Chen K, Risen J (2010) J Pers Soc Psychol 99:573-594] pointed out a serious methodological problem, which casts a doubt on the very existence of this choice-induced preference change as studied over the past 50 y. Here, using a proper control condition and two measures of preferences (self-report and brain activity), we found that the mere act of making a choice can change self-report preference as well as its neural representation (i.e., striatum activity), thus providing strong evidence for choice-induced preference change. Furthermore, our data indicate that the anterior cingulate cortex and dorsolateral prefrontal cortex tracked the degree of cognitive dissonance on a trial-by-trial basis. Our findings provide important insights into the neural basis of how actions can alter an individual's preferences.
根据许多现代经济理论，行动仅仅反映了个人的偏好，而一种被称为“认知失调”的心理现象则声称，行动也可以创造偏好。认知失调理论指出，在对两个同样偏好的项目进行艰难选择之后，拒绝一个喜欢的项目的行为会引起一种不舒服的感觉（认知失调），这反过来又激励个体改变他们的偏好以匹配他们之前的决定（即，减少对被拒绝项目的偏好）。然而，最近 Chen 和 Risen [Chen K, Risen J (2010) J Pers Soc Psychol 99:573-594] 指出了一个严重的方法论问题，这使得人们对过去 50 年来研究的这种选择引起的偏好变化的存在产生了怀疑。在这里，我们使用适当的对照条件和两种偏好测量方法（自我报告和大脑活动），发现仅仅做出选择的行为就可以改变自我报告的偏好及其神经表现（即纹状体活动），从而为选择引起的偏好变化提供了有力的证据。此外，我们的数据表明，前扣带皮层和背外侧前额叶皮层在逐次试验的基础上跟踪认知失调的程度。我们的发现为行动如何改变个体偏好的神经基础提供了重要的见解。
