Striatal D1 and D2 signaling differentially predict learning from positive and negative outcomes
Striatal D1 and D2 signaling differentially predict learning from positive and negative outcomes
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DOI：
10.1016/j.neuroimage.2014.12.070
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发表时间：
2015-04-01
期刊：
影响因子：
5.7
通讯作者：
Dagher, Alain
中科院分区：
文献类型：
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作者：
Cox, Sylvia M. L.;Frank, Michael J.;Dagher, Alain
我们从决策的积极和消极结果中学习的程度受到神经递质多巴胺的调节。多巴胺神经元因意外奖励而爆发，并因负面结果而暂停。假设这种双重信号机制可以驱动接近和回避行为。在这里，我们测试了源自计算强化学习模型的预测，其中方法是通过纹状体 D1 受体刺激导致的直接皮质纹状体通路的激活来介导的，而避免是通过继发于 D2 受体刺激减少的间接通路纹状体神经元的去抑制而发生的。使用具有两个独立放射性配体的正电子发射断层扫描，我们证明人类接近和回避学习的个体差异分别是通过纹状体 D1 和 D2 受体结合的变异性来预测的。此外，短暂的多巴胺前体消耗改善了对负面结果的学习。这些发现支持纹状体多巴胺通过分离的 D1 和 D2 皮质纹状体通路在奖励和回避学习中发挥双向调节作用。 (C) 2015 Elsevier Inc. 保留所有权利。
The extent to which we learn from positive and negative outcomes of decisions is modulated by the neurotransmitter dopamine. Dopamine neurons burst fire in response to unexpected rewards and pause following negative outcomes. This dual signaling mechanism is hypothesized to drive both approach and avoidance behavior. Here we test a prediction deriving from a computational reinforcement learning model, in which approach is mediated via activation of the direct cortico-striatal pathway due to striatal D1 receptor stimulation, while avoidance occurs via disinhibition of indirect pathway striatal neurons secondary to a reduction of D2 receptor stimulation. Using positron emission tomography with two separate radioligands, we demonstrate that individual differences in human approach and avoidance learning are predicted by variability in striatal D1 and D2 receptor binding, respectively. Moreover, transient dopamine precursor depletion improved learning from negative outcomes. These findings support a bidirectional modulatory role for striatal dopamine in reward and avoidance learning via segregated D1 and D2 cortico-striatal pathways. (C) 2015 Elsevier Inc. All rights reserved.