DO SEMANTIC CATEGORIES ACTIVATE DISTINCT CORTICAL REGIONS? EVIDENCE FOR A DISTRIBUTED NEURAL SEMANTIC SYSTEM
DO SEMANTIC CATEGORIES ACTIVATE DISTINCT CORTICAL REGIONS? EVIDENCE FOR A DISTRIBUTED NEURAL SEMANTIC SYSTEM
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DOI：
10.1080/02643290244000211
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发表时间：
2003-05
影响因子：
3.4
通讯作者：
Lorraine K. Tyler;Peter Bright;E. Dick;P. Tavares;Lea K. Pilgrim;Paul C. Fletcher;M. Greer;H. Moss
中科院分区：
文献类型：
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作者：
Lorraine K. Tyler;Peter Bright;E. Dick;P. Tavares;Lea K. Pilgrim;Paul C. Fletcher;M. Greer;H. Moss
认知神经科学中的一个关键问题是概念知识的神经表征。目前，争论的焦点集中在是否有专门用于处理特定语义属性或类别的神经区域，或者概念是否在未分化的神经系统中表示。对选择性语义缺陷患者的神经心理学研究和以前的神经影像学研究并不明确支持这两种解释。我们进行了PET研究，以确定是否有任何区域专业化的概念，从不同的语义类别，使用图片刺激和语义分类任务的处理。我们发现了一个从左下额叶皮层延伸到下颞叶，包括枕叶皮层和梭状回的大型语义网络的强大激活。我们发现的唯一类别效应是动物右枕叶皮层的额外激活，我们认为这是由于区分一种动物与另一种动物所需的额外视觉处理需求。我们还进行了分析，在特定的皮质区域，已声称优先激活的各种类别，但没有发现任何差异激活的功能类别的证据。我们解释这些数据的认知帐户的框架内，概念知识表示在一个无差别的分布式系统。
A key issue in cognitive neuroscience concerns the neural representation of conceptual knowledge. Currently, debate focuses around the issue of whether there are neural regions specialised for the processing of specific semantic attributes or categories, or whether concepts are represented in an undifferentiated neural system. Neuropsychological studies of patients with selective semantic deficits and previous neuroimaging studies do not unequivocally support either account. We carried out a PET study to determine whether there is any regional specialisation for the processing of concepts from different semantic categories using picture stimuli and a semantic categorisation task. We found robust activation of a large semantic network extending from left inferior frontal cortex into the inferior temporal lobe and including occipital cortex and the fusiform gyrus. The only category effect that we found was additional activation for animals in the right occipital cortex, which we interpret as being due to the extra visual processing demands required in order to differentiate one animal from another. We also carried out analyses in specific cortical regions that have been claimed to be preferentially activated for various categories, but found no evidence of any differential activation as a function of category. We interpret these data within the framework of cognitive accounts in which conceptual knowledge is represented within a nondifferentiated distributed system.