Department of Psychobiology and Neuroscience, Faculty of Psychology, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Department of Behavioral and Cognitive Neurobiology, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Queretaro, Mexico.
PLoS One. 2023 Sep 14;18(9):e0291558. doi: 10.1371/journal.pone.0291558. eCollection 2023.
Language comprehension involves both sub-lexical (e.g., phonological) and lexical-semantic processing. We conducted a task using functional magnetic resonance imaging (fMRI) to compare the processing of verbs in these two domains. Additionally, we examined the representation of concrete-motor and abstract-non-motor concepts by including two semantic categories of verbs: motor and mental. The findings indicate that sub-lexical processing during the reading of pseudo-verbs primarily involves the left dorsal stream of the perisylvian network, while lexical-semantic representation during the reading of verbs predominantly engages the ventral stream. According to the embodied or grounded cognition approach, modality-specific mechanisms (such as sensory-motor systems) and the well-established multimodal left perisylvian network contribute to the semantic representation of both concrete and abstract verbs. Our study identified the visual system as a preferential modality-specific system for abstract-mental verbs, which exhibited functional connectivity with the right crus I/lobule VI of the cerebellum. Taken together, these results confirm the dissociation between sub-lexical and lexical-semantic processing and provide neurobiological evidence of functional coupling between specific visual modality regions and the right cerebellum, forming a network that supports the semantic representation of abstract concepts. Further, the results shed light on the underlying mechanisms of semantic processing and contribute to our understanding of how the brain processes abstract concepts.
语言理解涉及亚词汇（如语音）和词汇语义处理。我们使用功能磁共振成像（fMRI）进行了一项任务，比较了这两个领域中动词的处理。此外，我们通过包括动词的两个语义类别：运动和心理，检查了具体运动和抽象非运动概念的表示。研究结果表明，在阅读假动词时，亚词汇处理主要涉及周围大脑皮层网络的左侧背流，而在阅读动词时，词汇语义表示主要涉及腹侧流。根据具身或扎根认知方法，特定模态的机制（如感觉运动系统）和成熟的多模态左侧大脑皮层网络有助于具体和抽象动词的语义表示。我们的研究确定了视觉系统是抽象心理动词的优先特定模态系统，它与小脑的右侧 Crus I/lobule VI 表现出功能连接。总之，这些结果证实了亚词汇和词汇语义处理之间的分离，并提供了特定视觉模态区域与右侧小脑之间功能耦合的神经生物学证据，形成了一个支持抽象概念语义表示的网络。此外，结果揭示了语义处理的潜在机制，有助于我们理解大脑如何处理抽象概念。
