How choice reveals and shapes expected hedonic outcome.
How choice reveals and shapes expected hedonic outcome.
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DOI：
10.1523/jneurosci.4972-08.2009
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发表时间：
2009-03-25
期刊：
影响因子：
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通讯作者：
Dolan RJ
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文献类型：
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作者：
Sharot T;De Martino B;Dolan RJ
人类倾向于改变自己的态度以与过去的行为保持一致。例如，在价值相似的替代方案之间进行选择后，人们将所选选项评价为比最初更好，而将拒绝的选项评价为更差。然而，尚不清楚这些评估的修改是否反映了刺激的预期享乐价值的生理表征以及我们对其的情绪反应的潜在变化。在这里，我们通过结合参与者对他们将从未来事件中获得的快乐的估计，以及他们在想象这些事件之前和之后进行选择时记录的大脑成像数据来解决这个问题。参与者在决策阶段后对选定的替代方案的评价相对于之前更好，而放弃的替代方案的价值较低。我们的功能磁共振成像研究结果表明，尾状核活动可以追踪选择后偏好的变化。具体来说，做出决定后，与所选刺激和拒绝刺激相关的 BOLD 信号差异会增强，反映了刚刚做出的选择。这一发现表明，刺激的预期享乐价值的生理表征会因对其的承诺而改变。此外，在决策过程引起的任何重估之前，我们的数据显示同一区域中的 BOLD 信号反映了我们稍后可能做出的选择。
Humans tend to modify their attitudes to align with past action. For example, after choosing between similarly valued alternatives, people rate the selected option as better than they originally did, and the rejected option as worse. However, it is unknown whether these modifications in evaluation reflect an underlying change in the physiological representation of a stimulus’ expected hedonic value and our emotional response to it. Here, we addressed this question by combining participants’ estimations of the pleasure they will derive from future events, with brain imaging data recorded while they imagined those events, both before, and after, choosing between them. Participants rated the selected alternatives as better after the decision stage relative to before, while discarded alternatives were valued less. Our fMRI findings reveal that post-choice changes in preference are tracked in caudate nucleus activity. Specifically, the difference in BOLD signal associated with the selected and rejected stimuli was enhanced after a decision was taken, reflecting the choice that had just been made. This finding suggests that the physiological representation of a stimulus’ expected hedonic value is altered by a commitment to it. Furthermore, prior to any revaluation induced by the decision process, our data show that BOLD signal in this same region reflects the choices we are likely to make at a later time.