Humans have a remarkable ability to understand what is and is not being said by conversational partners. It has been hypothesized that listeners decode the intended meaning of a communicative signal by assuming speakers speak cooperatively, rationally simulating the speaker’s choice process and inverting it to recover the speaker’s most probable meaning. We investigated whether and how rational simulations of speakers are represented in the listener’s brain, by combining referential communication games with functional neuroimaging. We show that listeners’ ventromedial prefrontal cortex encodes the probabilistic inference of what a cooperative speaker should say given a communicative goal and context, even when such inferences are irrelevant for reference resolution. The listener’s striatum encodes the amount of update on intended meaning, consistent with inverting a simulated mental model. These findings suggest a neural generative mechanism, subserved by the frontal-striatal circuits, that underlies our ability to understand communicative and, more generally, social actions.

人类具有非凡的能力来理解对话伙伴所说的话和没有说的话。有人假设，听众通过假设说话者合作说话、理性地模拟说话者的选择过程并将其反转以恢复说话者最可能的含义来解码通信信号的预期含义。我们通过将参考性交流游戏与功能性神经影像相结合，研究了说话者的理性模拟是否以及如何在听者的大脑中表现出来。我们表明，听众的腹内侧前额叶皮层对给定交际目标和上下文的合作说话者应该说的话进行概率推理编码，即使这种推理与参考解析无关。听者的纹状体对预期含义的更新量进行编码，这与反转模拟心理模型一致。这些发现表明，额叶-纹状体回路所支持的神经生成机制是我们理解交流以及更普遍的社会行为的能力的基础。