Faculty of Human Sciences, Institute of Psychology, Chair of Cognitive Neuroscience, University of Regensburg, 93053 Regensburg, Germany.
Faculty of Human Sciences, Institute of Psychology, Chair of Cognitive Neuroscience, University of Regensburg, 93053 Regensburg, Germany
J Neurosci. 2023 Nov 29;43(48):8219-8230. doi: 10.1523/JNEUROSCI.0700-22.2023.
Actions can be planned and recognized at different hierarchical levels, ranging from very specific (e.g., to swim backstroke) to very broad (e.g., locomotion). Understanding the corresponding neural representation is an important prerequisite to reveal how our brain flexibly assigns meaning to the world around us. To address this question, we conducted an event-related fMRI study in male and female human participants in which we examined distinct representations of observed actions at the subordinate, basic and superordinate level. Using multiple regression representational similarity analysis (RSA) in predefined regions of interest, we found that the three different taxonomic levels were best captured by patterns of activations in bilateral lateral occipitotemporal cortex (LOTC), showing the highest similarity with the basic level model. A whole-brain multiple regression RSA revealed that information unique to the basic level was captured by patterns of activation in dorsal and ventral portions of the LOTC and in parietal regions. By contrast, the unique information for the subordinate level was limited to bilateral occipitotemporal cortex, while no single cluster was obtained that captured unique information for the superordinate level. The behaviorally established action space was best captured by patterns of activation in the LOTC and superior parietal cortex, and the corresponding neural patterns of activation showed the highest similarity with patterns of activation corresponding to the basic level model. Together, our results suggest that occipitotemporal cortex shows a preference for the basic level model, with flexible access across the subordinate and the basic level. The human brain captures information at varying levels of abstraction. It is debated which brain regions host representations across different hierarchical levels, with some studies emphasizing parietal and premotor regions, while other studies highlight the role of the lateral occipitotemporal cortex (LOTC). To shed light on this debate, here we examined the representation of observed actions at the three taxonomic levels suggested by Rosch et al. (1976) Our results highlight the role of the LOTC, which hosts a shared representation across the subordinate and the basic level, with the highest similarity with the basic level model. These results shed new light on the hierarchical organization of observed actions and provide insights into the neural basis underlying the basic level advantage.
动作可以在不同的层次上进行规划和识别，从非常具体的（例如，仰泳）到非常广泛的（例如，运动）。理解相应的神经表示是揭示我们的大脑如何灵活地赋予周围世界意义的重要前提。为了解决这个问题，我们在男性和女性人类参与者中进行了一项基于事件的 fMRI 研究，在该研究中，我们检查了在从属、基本和上级水平观察到的动作的不同表示。使用多个回归代表性相似性分析 (RSA) 在预先定义的感兴趣区域中，我们发现三个不同的分类级别最好由双侧外侧枕颞叶皮层 (LOTC) 的激活模式来捕捉，与基本级别模型的相似性最高。全脑多个回归 RSA 显示，基本级别特有的信息由 LOTC 的背侧和腹侧部分以及顶叶区域的激活模式捕获。相比之下，从属级别特有的信息仅限于双侧枕颞叶皮层，而没有获得捕获上级级别特有的信息的单个集群。行为建立的动作空间最好由 LOTC 和顶叶上回的激活模式来捕捉，并且相应的神经激活模式与基本级别模型的激活模式具有最高的相似性。总之，我们的研究结果表明，外侧枕颞叶皮层对基本级别模型表现出偏好，并且可以灵活地访问从属级别和基本级别。人类大脑以不同的抽象层次捕获信息。哪些大脑区域在不同的层次上表示信息存在争议，一些研究强调顶叶和运动前区域，而其他研究则强调外侧枕颞叶皮层 (LOTC) 的作用。为了阐明这一争论，我们在这里检查了 Rosch 等人（1976 年）提出的三个分类水平上观察到的动作的表示。我们的结果强调了 LOTC 的作用，它在从属级别和基本级别之间具有共享的表示，与基本级别模型的相似性最高。这些结果为观察到的动作的层次结构组织提供了新的视角，并为基本级别优势的神经基础提供了深入的了解。
