Department of Neurosciences, Policlinico Gemelli, Catholic University of Rome, Italy.
Brain Cogn. 2011 Apr;75(3):299-309. doi: 10.1016/j.bandc.2010.12.001. Epub 2011 Jan 5.
In recent years, the anatomical and functional bases of conceptual activity have attracted a growing interest. In particular, Patterson and Lambon-Ralph have proposed the existence, in the anterior parts of the temporal lobes, of a mechanism (the 'amodal semantic hub') supporting the interactive activation of semantic representations in all modalities and for all semantic categories. The aim of then present paper is to discuss this model, arguing against the notion of an 'amodal' semantic hub, because we maintain, in agreement with the Damasio's construct of 'higher-order convergence zone', that a continuum exists between perceptual information and conceptual representations, whereas the 'amodal' account views perceptual informations only as a channel through which abstract semantic knowledge can be activated. According to our model, semantic organization can be better explained by two orthogonal higher-order convergence systems, concerning, on one hand, the right vs. left hemisphere and, on the other hand, the ventral vs. dorsal processing pathways. This model posits that conceptual representations may be mainly based upon perceptual activities in the right hemisphere and upon verbal mediation in the left side of the brain. It also assumes that conceptual knowledge based on the convergence of highly processed visual information with other perceptual data (and mainly concerning living categories) may be bilaterally represented in the anterior parts of the temporal lobes, whereas knowledge based on the integration of visual data with action schemata (namely knowledge of actions, body parts and artefacts) may be more represented in the left fronto-temporo-parietal areas.
近年来，概念活动的解剖学和功能基础引起了越来越多的关注。特别是，Patterson 和 Lambon-Ralph 提出，在前颞叶区域存在一种机制（“非模态语义中枢”），支持所有模态和所有语义类别中语义表示的交互激活。本文旨在讨论该模型，反对“非模态”语义中枢的概念，因为我们同意达马西奥的“高阶汇聚区”的观点，认为感知信息和概念表示之间存在连续体，而“非模态”的解释仅将感知信息视为可以激活抽象语义知识的通道。根据我们的模型，语义组织可以通过两个正交的高阶汇聚系统得到更好的解释，一方面涉及左右半球，另一方面涉及腹侧和背侧处理途径。该模型假设，概念表示可能主要基于右半球的感知活动和大脑左半球的言语中介。它还假设，基于高度处理的视觉信息与其他感知数据（主要涉及生命范畴）的汇聚的概念知识可能在前颞叶区域双侧表示，而基于视觉数据与动作图式（即动作、身体部位和人工制品的知识）整合的概念知识可能更多地在前额颞顶叶区域表示。
