Distinct model-free and model-based learning processes are thought to drive both typical and dysfunctional behaviours. Data from two-stage decision tasks have seemingly shown that human behaviour is driven by both processes operating in parallel. However, in this study, we show that more detailed task instructions lead participants to make primarily model-based choices that have little, if any, simple model-free influence. We also demonstrate that behaviour in the two-stage task may falsely appear to be driven by a combination of simple model-free and model-based learning if purely model-based agents form inaccurate models of the task because of misconceptions. Furthermore, we report evidence that many participants do misconceive the task in important ways. Overall, we argue that humans formulate a wide variety of learning models. Consequently, the simple dichotomy of model-free versus model-based learning is inadequate to explain behaviour in the two-stage task and connections between reward learning, habit formation and compulsivity.

不同的无模型和基于模型的学习过程被认为会驱动典型和功能失调的行为。来自两阶段决策任务的数据似乎表明，人类行为是由两个并行运行的过程驱动的。然而，在这项研究中，我们表明更详细的任务说明会导致参与者主要做出基于模型的选择，而这些选择几乎没有（如果有的话）简单的无模型影响。我们还证明，如果纯基于模型的代理由于误解而形成不准确的任务模型，则两阶段任务中的行为可能错误地似乎是由简单的无模型和基于模型的学习组合驱动的。此外，我们报告的证据表明，许多参与者确实在重要方面误解了任务。总的来说，我们认为人类制定了各种各样的学习模型。最后，