Ventromedial and dorsolateral prefrontal interactions underlie will to fight and die for a cause

Abstract Willingness to fight and die (WFD) has been developed as a measure to capture willingness to incur costly sacrifices for the sake of a greater cause in the context of entrenched conflict. WFD measures have been repeatedly used in field studies, including studies on the battlefield, although their neurofunctional correlates remain unexplored. Our aim was to identify the neural underpinnings of WFD, focusing on neural activity and interconnectivity of brain areas previously associated with value-based decision-making, such as the ventromedial prefrontal cortex (vmPFC) and the dorsolateral prefrontal cortex (dlPFC). A sample of Pakistani participants supporting the Kashmiri cause was selected and invited to participate in an functional magnetic resonance (fMRI) paradigm where they were asked to convey their WFD for a series of values related to Islam and current politics. As predicted, higher compared to lower WFD was associated with increased ventromedial prefrontal activity and decreased dorsolateral activity, as well as lower connectivity between the vmPFC and the dlPFC. Our findings suggest that WFD more prominently relies on brain areas typically associated with subjective value (vmPFC) rather than integration of material costs (dlPFC) during decision-making, supporting the notion that decisions on costly sacrifices may not be mediated by cost-benefit computation.

摘要 战斗和牺牲意愿（WFD）已被开发为一种衡量指标，用于在根深蒂固的冲突背景下捕捉为了更伟大的事业而承受高昂牺牲的意愿。战斗和牺牲意愿的测量方法已在实地研究中反复使用，包括在战场上的研究，尽管其神经功能相关性仍未被探索。我们的目的是确定战斗和牺牲意愿的神经基础，重点关注先前与基于价值的决策相关的大脑区域的神经活动和相互连接性，例如腹内侧前额叶皮层（vmPFC）和背外侧前额叶皮层（dlPFC）。选择了一批支持克什米尔事业的巴基斯坦参与者，并邀请他们参与功能性磁共振成像（fMRI）范式，在该范式中，他们被要求针对一系列与伊斯兰教和当前政治相关的价值观表达他们的战斗和牺牲意愿。正如所预测的那样，较高的战斗和牺牲意愿与腹内侧前额叶活动增加、背外侧活动减少以及腹内侧前额叶皮层和背外侧前额叶皮层之间的连接性降低相关。我们的研究结果表明，在决策过程中，战斗和牺牲意愿更显著地依赖于通常与主观价值（腹内侧前额叶皮层）相关的大脑区域，而非物质成本的整合（背外侧前额叶皮层），这支持了关于高昂牺牲的决策可能不是由成本效益计算所介导的观点。