Center for Magnetic Resonance Imaging of the Brain, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
Neuropsychologia. 2010 Sep;48(11):3198-204. doi: 10.1016/j.neuropsychologia.2010.06.031. Epub 2010 Jul 1.
This study examined the neural basis of framing effects using life-death decision problems framed either positively in terms of lives saved or negatively in terms of lives lost in large group and small group contexts. Using functional MRI we found differential brain activations to the verbal and social cues embedded in the choice problems. In large group contexts, framing effects were significant where participants were more risk seeking under the negative (loss) framing than under the positive (gain) framing. This behavioral difference in risk preference was mainly regulated by the activation in the right inferior frontal gyrus, including the homologue of the Broca's area. In contrast, framing effects diminished in small group contexts while the insula and parietal lobe in the right hemisphere were distinctively activated, suggesting an important role of emotion in switching choice preference from an indecisive mode to a more consistent risk-taking inclination, governed by a kith-and-kin decision rationality.
这项研究使用生活-死亡决策问题，在大群体和小群体情境下分别以积极的挽救生命的方式和消极的失去生命的方式来构建框架，以此来研究框架效应的神经基础。使用功能磁共振成像，我们发现了对选择问题中嵌入的语言和社会线索的不同大脑激活。在大群体情境下，当参与者在负面（损失）框架下比在正面（收益）框架下更倾向于冒险时，就会出现框架效应。这种风险偏好的行为差异主要受到右额下回（包括布罗卡区同源区）的激活调节。相比之下，当右半球的岛叶和顶叶明显活跃时，框架效应在小群体情境下会减弱，这表明情绪在将选择偏好从犹豫不决的模式切换到更一致的冒险倾向方面起着重要作用，这种倾向受亲缘决策理性的控制。
