Ventral striatum's role in learning from gains and losses.
Ventral striatum's role in learning from gains and losses.
复制标题
腹侧纹状体在从得失中学习的作用。
DOI：
10.1073/pnas.1809833115
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发表时间：
2018
影响因子：
11.1
通讯作者：
Averbeck,BrunoB
中科院分区：
文献类型：
--
作者：
Taswell,CraigA;Costa,VincentD;Murray,ElisabethA;Averbeck,BrunoB
适应行为需要动物从经验中学习。理想情况下，学习既应该促进带来回报的选择，也应该减少导致损失的选择。由于腹侧纹状体(VS)含有对厌恶刺激做出反应的神经元，而厌恶刺激可以推动VS释放多巴胺，因此VS可能有助于了解包括损失在内的厌恶结果。然而，其他研究表明，VS可能在学习在奖励中进行选择方面发挥着特定的作用，而其他系统则在从厌恶结果中进行学习的过程中发挥中介作用。为了检验VS在学习得失中的作用，我们比较了猕猴与VS损伤和未手术对照组在强化学习任务中的表现。在这项任务中，猴子们得到或丢失了代币，这些代币定期被兑换成果汁，作为选择的结果。他们在试验中学会了选择与收益相关的线索，而不是选择与损失相关的线索。我们发现，患有VS损伤的猴子在学习在奖励大小不同的线索之间做出选择方面存在缺陷。相比之下，当选择涉及潜在损失时，患有VS损害的猴子表现得与对照组一样好。我们还将强化学习模型与行为相匹配，并比较了不同组之间的学习率。与对照组相比，有VS病变的猴子对获得线索的学习速度降低。因此，在这项任务中，VS在学习在奖励选项之间做出选择方面扮演着特殊的角色。
Adaptive behavior requires animals to learn from experience. Ideally, learning should both promote choices that lead to rewards and reduce choices that lead to losses. Because the ventral striatum (VS) contains neurons that respond to aversive stimuli and aversive stimuli can drive dopamine release in the VS, it is possible that the VS contributes to learning about aversive outcomes, including losses. However, other work suggests that the VS may play a specific role in learning to choose among rewards, with other systems mediating learning from aversive outcomes. To examine the role of the VS in learning from gains and losses, we compared the performance of macaque monkeys with VS lesions and unoperated controls on a reinforcement learning task. In the task, the monkeys gained or lost tokens, which were periodically cashed out for juice, as outcomes for choices. They learned over trials to choose cues associated with gains, and not choose cues associated with losses. We found that monkeys with VS lesions had a deficit in learning to choose between cues that differed in reward magnitude. By contrast, monkeys with VS lesions performed as well as controls when choices involved a potential loss. We also fit reinforcement learning models to the behavior and compared learning rates between groups. Relative to controls, the monkeys with VS lesions had reduced learning rates for gain cues. Therefore, in this task, the VS plays a specific role in learning to choose between rewarding options.