The human brain creates an external world representation based on magnitude judgments by estimating distance, numerosity, or size. The magnitude and spatial representation are hypothesized to rely on common mechanisms shared by different sensory modalities. We explored the relationship between magnitude and spatial representation using two different sensory systems. We hypothesize that the interaction between space and magnitude is combined differently depending on sensory modalities. Furthermore, we aimed to understand the role of the spatial reference frame in magnitude representation. We used stimulus–response compatibility (SRC) to investigate these processes assuming that performance is improved if stimulus and response share common features. We designed an auditory and tactile SRC task with conflicting spatial and magnitude mapping. Our results showed that sensory modality modulates the relationship between space and magnitude. A larger effect of magnitude over spatial congruency occurred in a tactile task. However, magnitude and space showed similar weight in the auditory task, with neither spatial congruency nor magnitude congruency having a significant effect. Moreover, we observed that the spatial frame activated during tasks was elicited by the sensory inputs. The participants' performance was reversed in the tactile task between uncrossed and crossed hands posture, suggesting an internal coordinate system. In contrast, crossing the hands did not alter performance (i.e., using an allocentric frame of reference). Overall, these results suggest that space and magnitude interaction differ in auditory and tactile modalities, supporting the idea that these sensory modalities use different magnitude and spatial representation mechanisms.

人脑通过估计距离、数量或大小，根据大小判断创建外部世界表示。假设幅度和空间表示依赖于不同感觉方式共享的共同机制。我们使用两种不同的感觉系统探索了幅度和空间表示之间的关系。我们假设空间和幅度之间的相互作用根据感觉方式以不同的方式组合。此外，我们旨在了解空间参考系在幅度表示中的作用。我们使用刺激-反应相容性 (SRC) 来研究这些过程，假设如果刺激和反应具有共同特征，则性能会得到改善。我们设计了一个具有冲突空间和幅度映射的听觉和触觉 SRC 任务。我们的研究结果表明，感觉方式调节空间和大小之间的关系。在触觉任务中，幅度对空间一致性的影响更大。然而，幅度和空间在听觉任务中表现出相似的权重，空间一致性和幅度一致性都没有显着影响。此外，我们观察到在任务期间激活的空间框架是由感官输入引发的。参与者在未交叉和交叉手姿势之间的触觉任务中的表现是相反的，这表明内部坐标系。相比之下，双手交叉并没有改变表现（即，使用异中心参照系）。总体而言，这些结果表明空间和幅度相互作用在听觉和触觉方式上有所不同，