Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08540, and Department of Psychology, Harvard University, Cambridge, Massachusetts 02138.
J Neurosci. 2014 Mar 26;34(13):4741-9. doi: 10.1523/JNEUROSCI.3390-13.2014.
A decade's research highlights a critical dissociation between automatic and controlled influences on moral judgment, which is subserved by distinct neural structures. Specifically, negative automatic emotional responses to prototypically harmful actions (e.g., pushing someone off of a footbridge) compete with controlled responses favoring the best consequences (e.g., saving five lives instead of one). It is unknown how such competitions are resolved to yield "all things considered" judgments. Here, we examine such integrative moral judgments. Drawing on insights from research on self-interested, value-based decision-making in humans and animals, we test a theory concerning the respective contributions of the amygdala and ventromedial prefrontal cortex (vmPFC) to moral judgment. Participants undergoing fMRI responded to moral dilemmas, separately evaluating options for their utility (Which does the most good?), emotional aversiveness (Which feels worse?), and overall moral acceptability. Behavioral data indicate that emotional aversiveness and utility jointly predict "all things considered" integrative judgments. Amygdala response tracks the emotional aversiveness of harmful utilitarian actions and overall disapproval of such actions. During such integrative moral judgments, the vmPFC is preferentially engaged relative to utilitarian and emotional assessments. Amygdala-vmPFC connectivity varies with the role played by emotional input in the task, being the lowest for pure utilitarian assessments and the highest for pure emotional assessments. These findings, which parallel those of research on self-interested economic decision-making, support the hypothesis that the amygdala provides an affective assessment of the action in question, whereas the vmPFC integrates that signal with a utilitarian assessment of expected outcomes to yield "all things considered" moral judgments.
一项长达十年的研究强调了自动和控制对道德判断的影响之间存在关键的分离，这种分离由不同的神经结构来支持。具体来说，对典型有害行为（例如，将某人推下人行天桥）的负面自动情绪反应与支持最佳结果（例如，拯救五条生命而不是一条生命）的控制反应相竞争。目前尚不清楚如何解决这些竞争以产生“全面考虑”的判断。在这里，我们研究了这种综合的道德判断。借鉴人类和动物基于自我利益的价值决策研究的见解，我们检验了一个关于杏仁核和腹内侧前额叶皮层（vmPFC）对道德判断的各自贡献的理论。接受 fMRI 的参与者对道德困境做出反应，分别评估其效用（哪种方法带来的好处最多？）、情绪厌恶（哪种感觉更糟？）和整体道德可接受性。行为数据表明，情绪厌恶和效用共同预测“全面考虑”的综合判断。杏仁核反应追踪有害功利行为的情绪厌恶和对这种行为的整体不赞成。在这种综合的道德判断中，vmPFC 相对于功利和情绪评估更优先参与。杏仁核-vmPFC 的连接性随情绪输入在任务中的作用而变化，对于纯功利评估最低，对于纯情绪评估最高。这些发现与研究自我利益的经济决策的发现相似，支持了这样一种假设，即杏仁核对所讨论的行为提供了情感评估，而 vmPFC 则将该信号与对预期结果的功利评估相结合，从而产生“全面考虑”的道德判断。
