Striatal Dopamine Can Enhance Both Fast Working Memory-Based Learning, and Slow Reinforcement Learning, and Also Make Learning Less Effort-Costly

Associations can be learned incrementally, via reinforcement learning (RL), or stored instantly in working memory (WM). While WM is fast, it is also capacity-limited and effortful. Striatal dopamine may promote RL plasticity, and WM, by facilitating updating and effort exertion. Yet, prior studies have failed to distinguish between dopamine’s effects on RL versus WM. N = 100 participants completed a paradigm isolating these systems in a double-blind study measuring dopamine synthesis with [18F]-FDOPA PET imaging and manipulating dopamine with methylphenidate and sulpiride. We find that learning is enhanced among high synthesis capacity individuals and by methylphenidate, but impaired by sulpiride. Methylphenidate also blunts implicit effort cost learning. Computational modeling reveals that individuals with higher dopamine synthesis rely more on WM, while methylphenidate boosts their RL rates. The D2 receptor antagonist sulpiride reduces accuracy due to diminished WM involvement and faster WM decay. We conclude that dopamine enhances both slow RL, and fast WM, by promoting plasticity and reducing implicit effort sensitivity.

This dataset contains the final data derivatives and analysis code to produce the results presented in the paper. The raw data for the project can be found in a separate repository: https://doi.org/10.34973/wn51-ej53

关联信息可通过强化学习（Reinforcement Learning, RL）逐步习得，亦可即时存储于工作记忆（Working Memory, WM）中。尽管工作记忆的处理速度较快，但同时存在容量限制且需要投入认知努力。纹状体多巴胺可通过促进更新过程与认知努力投入，同时强化强化学习的神经可塑性与工作记忆功能。然而，此前的研究未能区分多巴胺对强化学习与工作记忆的差异化影响。
本研究共招募100名参与者，采用分离这两个认知系统的实验范式，开展了一项双盲研究：通过[18F]-FDOPA正电子发射断层扫描（PET）成像测量受试者的多巴胺合成水平，并分别使用哌甲酯与舒必利对多巴胺系统进行药理学调控。研究结果显示，多巴胺合成能力较高的个体学习能力得到增强，哌甲酯也可提升学习表现，而舒必利则会损害学习能力。此外，哌甲酯还会削弱内隐认知努力成本的学习效应。
计算建模分析表明，多巴胺合成水平更高的个体更多依赖工作记忆，而哌甲酯则提升了他们的强化学习速率。作为D2受体拮抗剂的舒必利，会因降低工作记忆的参与度并加快工作记忆衰减速度，导致任务准确率下降。综上，多巴胺可通过促进神经可塑性并降低内隐认知努力敏感性，同时强化缓慢的强化学习与快速的工作记忆功能。

本数据集包含用于复现本论文各项结果的最终数据衍生文件与分析代码。本项目的原始数据可在独立仓储库中获取：https://doi.org/10.34973/wn51-ej53