Neural mechanism of intertemporal choice: From discounting future gains to future losses
Neural mechanism of intertemporal choice: From discounting future gains to future losses
复制标题
跨期选择的神经机制：从未来收益贴现到未来损失
DOI：
10.1016/j.brainres.2008.12.061
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发表时间：
2009-03-19
期刊：
影响因子：
2.9
通讯作者：
Jiang, Tianzi
中科院分区：
文献类型：
--
作者：
Xu, Lijuan;Liang, Zhu-Yuan;Jiang, Tianzi
跨期选择是指在不同时间点发生的结果之间的权衡，它不仅涉及收益选项，还涉及与成本相关的选项。先前的神经影像学研究主要关注对未来收益的贴现；因此，对未来损失进行贴现的神经机制仍未明确。利用事件相关功能性磁共振成像，我们通过两个具有对称收益和损失模式的决策任务，全面研究了时间贴现的神经机制。我们的研究结果显示，在对未来收益和未来损失进行贴现时，外侧前额叶和后顶叶区域均被激活，但在贴现损失时其激活程度更强。此外，我们发现，在涉及损失的跨期选择过程中，脑岛、丘脑和背侧纹状体的激活程度更高，这表明对损失的敏感性增强可能是由负面情绪驱动的。另外，当选择包括即时选项时，后扣带回皮质和内侧前额叶皮质被激活，而当选择涉及即时损失时，包括前扣带回皮质、脑岛和额上回在内的其他区域会优先被激活。综上所述，我们的研究结果表明，一个额顶网络支持常见的贴现过程，更重要的是，对未来损失和收益的贴现在大脑中是不对称的。我们推测，这可能为未来损失的贴现斜率小于未来收益这一现象提供了神经学基础。（C）2008爱思唯尔有限公司。保留所有权利。
Intertemporal choice, the tradeoff among outcomes occurring at different points in time, involves not only benefit options but also those associated with cost. Previous neuroimaging studies have primarily focused on discounting future gains; thus the neural mechanism underlying discounting future losses remains unidentified. Using event-related functional magnetic resonance imaging, we comprehensively investigated the neural mechanism of temporal discounting using two decision-making tasks with a symmetric pattern of gains and losses. Our results revealed that the lateral prefrontal and posterior parietal areas were activated in discounting both future gains and future losses, but their activations were stronger when discounting losses. Moreover, we found that the insula, thalamus and dorsal striatum were more activated during intertemporal choices involving losses, suggesting that the enhanced sensitivity to losses may be driven by negative emotions. In addition, whereas the posterior cingulate cortex and medial prefrontal cortex were activated when the choices included immediate options, extra regions including the anterior cingulate cortex, insula and superior frontal gyrus were preferentially activated when the choices involved immediate losses. Taken together, our findings suggest that a fronto-parietal network supports the common discounting process, and more importantly, discounting future losses and gains occurs asymmetrically in the brain. We speculate that this may provide a neural basis for the phenomenon that future losses are discounted less steeply than future gains. (C) 2008 Elsevier B.V. All rights reserved.