Department of Chinese and Bilingual Studies, The Hong Kong Polytechnic University, Hong Kong, SAR, China.
Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
Cognition. 2025 Jan;254:105951. doi: 10.1016/j.cognition.2024.105951. Epub 2024 Sep 13.
Different organizational structures have been argued to underlie semantic knowledge about concepts; taxonomic organization, based on shared features, and thematic organization based on co-occurrence in common scenes and scenarios. The goal of the current study is to examine which of the two organizational systems are more engaged in the semantic context of a picture naming task. To address this question, we examined the representational structure underlying the semantic space in different picture naming tasks by applying representational similarity analysis (RSA) to electroencephalography (EEG) datasets. In a series of experiments, EEG signals were collected while participants named pictures under different semantic contexts. Study 1 reanalyzes existing data from semantic contexts directing attention to taxonomic organization and semantic contexts that are not biased towards either taxonomic or thematic organization. In Study 2 we keep the stimuli the same and vary semantic contexts to draw attention to either taxonomic or thematic organization. The RSA approach allows us to examine the pairwise similarity in scalp-recorded amplitude patterns at each time point following the onset of the picture and relate it to theoretical taxonomic and thematic measures derived from computational models of semantics. Across all tasks, the similarity structure of scalp-recorded neural activity correlated better with taxonomic than thematic measures, in time windows associated with semantic processing. Most strikingly, we found that the scalp-recorded patterns of neural activity between taxonomically related items were more similar to each other than the scalp-recorded patterns of neural activity for thematically related or unrelated items, even in tasks that makes thematic information more salient. These results suggest that the principle semantic organization of these concepts during picture naming is taxonomic, at least in the context of picture naming.
不同的组织结构被认为是语义知识的基础，这些组织结构包括基于共同特征的分类组织和基于共同场景和情境共现的主题组织。本研究的目的是检验这两种组织系统在图片命名任务的语义语境中哪个更重要。为了解决这个问题，我们通过应用代表性相似性分析（RSA）对脑电图（EEG）数据集进行分析，来检验不同图片命名任务的语义空间的表示结构。在一系列实验中，当参与者在不同的语义语境下命名图片时，我们收集了 EEG 信号。研究 1 重新分析了来自语义语境的现有数据，这些语义语境分别关注分类组织和不偏向分类或主题组织的语义语境。在研究 2 中，我们保持刺激不变，改变语义语境，以吸引人们关注分类或主题组织。RSA 方法允许我们在图片呈现后每个时间点检查头皮记录的幅度模式的成对相似性，并将其与源自语义计算模型的理论分类和主题措施相关联。在所有任务中，头皮记录的神经活动相似性结构与分类措施比主题措施更相关，在与语义处理相关的时间窗口中。最引人注目的是，我们发现，在与主题相关或不相关的项目的头皮记录的神经活动模式之间，分类相关项目的头皮记录的神经活动模式彼此之间更相似，即使在使主题信息更突出的任务中也是如此。这些结果表明，在图片命名过程中，这些概念的主要语义组织至少在图片命名的语境中是分类的。
