Zheng Ya, Li Qi, Wang Kai, Wu Haiyan, Liu Xun
Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
University of Chinese Academy of Sciences, Beijing, China.
Psychophysiology. 2015 Jul;52(7):895-904. doi: 10.1111/psyp.12415. Epub 2015 Feb 9.
A well-known bias in risky decision making is that most people tend to be risk averse when gains are salient but risk seeking when losses are salient. The present study addressed the neural dynamics of this process by recording ERPs during a gambling task in a gain and a loss context. Behaviorally, participants were found to be risk averse in the gain context but risk neutral in the loss context. During the anticipation stage, an increased stimulus-preceding negativity was elicited by high- versus low-risk choices in the gain but not the loss context. During the outcome-appraisal stage, the feedback-related negativity was larger after high- versus low-risk choices in the gain instead of the loss context. For the P300, an outcome valence effect (a larger P300 for gain vs. loss outcomes) emerged following the high- versus low-risk decisions in the gain but not the loss context. Our findings suggest that risk processing can be modulated by the context of valence during the anticipation stage and by both the contextual valence and the outcome valence during the outcome-appraisal stage, which may be driven by the motivational salience imposed by the context of valence.
风险决策中一个众所周知的偏差是，大多数人在收益显著时往往规避风险，而在损失显著时则寻求风险。本研究通过在收益和损失情境下的赌博任务中记录事件相关电位（ERP），探讨了这一过程的神经动力学。行为学上，发现参与者在收益情境中规避风险，但在损失情境中风险中性。在预期阶段，在收益而非损失情境中，高风险与低风险选择会引发刺激前负波增强。在结果评估阶段，在收益而非损失情境中，高风险与低风险选择后反馈相关负波更大。对于P300，在收益而非损失情境中，高风险与低风险决策后出现了结果效价效应（收益结果比损失结果的P300更大）。我们的研究结果表明，风险处理在预期阶段可由效价情境调节，在结果评估阶段可由情境效价和结果效价共同调节，这可能由效价情境施加的动机显著性驱动。
