Yanagisawa Kuniaki, Kashima Emiko S, Shigemune Yayoi, Nakai Ryusuke, Abe Nobuhito
Department of Psychology, Graduate School of Humanities, Kobe University, Kobe 657-8501 Japan.
School of Psychology and Public Health, La Trobe University, Bundoora, Vic 3086, Australia.
Cereb Cortex Commun. 2021 Feb 22;2(2):tgab013. doi: 10.1093/texcom/tgab013. eCollection 2021.
Death is an important reminder that our lives are finite. Although some studies have shown that thinking about one's own death increases temporal discounting (i.e., the devaluing of future rewards), the underlying neural mechanisms are still unknown. In a functional magnetic resonance imaging experiment, we compared the neural and behavioral processes of temporal discounting across four conditions involving distinct types of future thinking (death related, negative, neutral, and positive). Replicating prior research, the behavioral evidence showed that temporal discounting increased when thinking about one's own future death. Multivoxel pattern analysis showed that death-related future thinking was decoded in default mode regions, including the inferior parietal lobule, precuneus, and medial prefrontal cortex (MPFC). When future thinking was death related (vs. negative), increased temporal discounting was associated with a higher decoding accuracy in the precuneus and MPFC. The present findings suggest that death-related neural representations are distributed across default mode regions, and neural populations in the cortical midline structures play a crucial role in the integration of one's own death into economic decision-making.
死亡是一个重要的提醒，它让我们明白生命是有限的。尽管一些研究表明，思考自己的死亡会增加时间折扣（即对未来奖励的贬值），但其潜在的神经机制仍然未知。在一项功能磁共振成像实验中，我们比较了四种涉及不同类型未来思考（与死亡相关、消极、中性和积极）的条件下时间折扣的神经和行为过程。重复先前的研究，行为证据表明，思考自己未来的死亡时时间折扣会增加。多体素模式分析表明，与死亡相关的未来思考在默认模式区域被解码，包括下顶叶小叶、楔前叶和内侧前额叶皮质（MPFC）。当未来思考与死亡相关（相对于消极）时，时间折扣增加与楔前叶和MPFC中更高的解码准确性相关。目前的研究结果表明，与死亡相关的神经表征分布在默认模式区域，皮质中线结构中的神经群体在将自己的死亡整合到经济决策中起着关键作用。
