Two spatiotemporally distinct value systems shape reward-based learning in the human brain.
Two spatiotemporally distinct value systems shape reward-based learning in the human brain.
复制标题
DOI：
10.1038/ncomms9107
复制
发表时间：
2015-09-08
影响因子：
16.6
通讯作者：
Philiastides MG
中科院分区：
文献类型：
--
作者：
Fouragnan E;Retzler C;Mullinger K;Philiastides MG
避免重复的错误和学习加强奖励的决定是人类生存和适应行动的关键。然而，编码不同决策结果的价值体系的神经基础仍然难以捉摸。在这里耦合单次试验脑电图与同时获得的功能磁共振成像，我们揭示了两个独立的，但相互作用的价值系统编码的决策结果的时空动态。与调节警觉性和转换行为的作用相一致，早期系统仅由负面结果激活，并参与唤醒相关和运动准备的大脑结构。与基于奖励的学习中的角色一致，后来的系统分别对消极和积极的结果做出不同的抑制或激活人类奖励网络的区域。在负面结果之后，早期系统通过丘脑与腹侧纹状体的相互作用与晚期系统相互作用并下调晚期系统。重要的是，这种耦合的强度预测参与者的转换行为和回避学习，直接涉及丘脑纹状体通路的奖励为基础的学习。 学会强化奖励决策和避免重复错误是至关重要的，但在价值导向选择中调节反馈处理的神经系统仍然难以捉摸。在这里，作者揭示了学习过程中两个独立但相互作用的价值系统的时空动态。
Avoiding repeated mistakes and learning to reinforce rewarding decisions is critical for human survival and adaptive actions. Yet, the neural underpinnings of the value systems that encode different decision-outcomes remain elusive. Here coupling single-trial electroencephalography with simultaneously acquired functional magnetic resonance imaging, we uncover the spatiotemporal dynamics of two separate but interacting value systems encoding decision-outcomes. Consistent with a role in regulating alertness and switching behaviours, an early system is activated only by negative outcomes and engages arousal-related and motor-preparatory brain structures. Consistent with a role in reward-based learning, a later system differentially suppresses or activates regions of the human reward network in response to negative and positive outcomes, respectively. Following negative outcomes, the early system interacts and downregulates the late system, through a thalamic interaction with the ventral striatum. Critically, the strength of this coupling predicts participants' switching behaviour and avoidance learning, directly implicating the thalamostriatal pathway in reward-based learning. Learning to reinforce rewarding decisions and avoiding repeated mistakes is critical, yet the neural systems mediating feedback processing in value-guided choices remain elusive. Here the authors uncover the spatiotemporal dynamics of two separate but interacting value systems during learning.