Multiple Dopamine Systems: Weal and Woe of Dopamine.
Multiple Dopamine Systems: Weal and Woe of Dopamine.
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多重多巴胺系统：多巴胺的福与祸。
DOI：
10.1101/sqb.2018.83.037648
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Uchida,Naoshige
中科院分区：
文献类型：
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作者：
Watabe-Uchida,Mitsuko;Uchida,Naoshige
预测未来结果的能力提高了动物的适应性。数十年的研究表明，多巴胺神经元会传播奖励预测误差（RPE）信号（实际奖励与预测奖励之间的差异），以推动学习以预测未来的结果。然而，最近的研究开始表明，多巴胺神经元比之前想象的更加多样化。在这篇综述中，我们将总结一系列研究，这些研究显示了投射到纹状体（TS）后“尾部”的多巴胺神经元在解剖学、活动和功能方面的独特特性。具体来说，TS 投射的多巴胺神经元会被一部分负面事件（包括来自新物体的威胁）激活，发送对外部威胁的预测错误，并强化回避行为。这些结果表明，大脑中至少有两个多巴胺介导的强化学习轴——一个从规范的 RPE 中学习，另一个从威胁预测错误中学习。我们认为，多个学习系统的存在是一种自适应策略，使每个系统能够根据自己的需求进行优化。哺乳动物纹状体的区室组织类似于昆虫（蘑菇体）的多巴胺受体区域，这表明多巴胺功能在整个门中保守。
The ability to predict future outcomes increases the fitness of the animal. Decades of research have shown that dopamine neurons broadcast reward prediction error (RPE) signals—the discrepancy between actual and predicted reward—to drive learning to predict future outcomes. Recent studies have begun to show, however, that dopamine neurons are more diverse than previously thought. In this review, we will summarize a series of our studies that have shown unique properties of dopamine neurons projecting to the posterior “tail” of the striatum (TS) in terms of anatomy, activity, and function. Specifically, TS-projecting dopamine neurons are activated by a subset of negative events including threats from a novel object, send prediction errors for external threats, and reinforce avoidance behaviors. These results indicate that there are at least two axes of dopamine-mediated reinforcement learning in the brain—one learning from canonical RPEs and another learning from threat prediction errors. We argue that the existence of multiple learning systems is an adaptive strategy that makes possible each system optimized for its own needs. The compartmental organization in the mammalian striatum resembles that of a dopamine-recipient area in insects (mushroom body), pointing to a principle of dopamine function conserved across phyla.