Lambon Ralph M A, Patterson K, Hodges J R
Department of Psychology, University of York, U.K.
Neuropsychologia. 1997 Sep;35(9):1251-60. doi: 10.1016/s0028-3932(97)00052-3.
We studied the relationship between naming and semantic memory in a group of 10 patients with dementia of Alzheimer's type. In an extension to a previous cross-sectional study (Hodges, J. R. et al., Brain and Language, 1996, 54, 302-325), this relationship was investigated at two longitudinal points within each patient's cognitive decline. Two types of naming performance were compared: items that each patient named correctly at the first stage but failed to name at the second stage, as contrasted with items named correctly at both stages (thereby providing a control for cognitive decline in general). Semantic knowledge of the concepts represented by the pictures in the naming test was investigated at each stage using definitions to the spoken object name, scored particularly for the number of sensory and associative/functional features provided by the patient. At stage 2, an analysis of the definitions for named-->unnamed items as contrasted with named-->named objects revealed a significant loss of both sensory and associative information. A comparison between natural kinds (animals and birds) and artefacts (household objects, vehicles, etc.), however, demonstrated a striking interaction between category and type of information contained in the definitions. Specifically, stage 2 definitions of artefacts in the named-->unnamed set showed a disproportionate loss of associative/functional information, while definitions of animal names that patients failed to produce in response to the pictures were notably lacking in sensory features. This pattern supports the notion that successful naming relies on a subset of critical semantic features which vary somewhat across different categories of semantic knowledge. We suggest that these findings are best encompassed by a conception of semantic organization, Weighted Overlappingly Organized Features (WOOF), in which (i) knowledge about all objects is represented by a central, distributed network of features activated by both words and pictures, but (ii) natural kinds and artefacts are differentially weighted in favour of those features that are involved in learning about and experiencing different kinds of objects.
我们对一组10名阿尔茨海默病型痴呆患者的命名与语义记忆之间的关系进行了研究。作为之前一项横断面研究（霍奇斯，J.R.等人，《大脑与语言》，1996年，第54卷，第302 - 325页）的扩展，我们在每位患者认知衰退的两个纵向时间点对这种关系进行了调查。比较了两种命名表现类型：每位患者在第一阶段正确命名但在第二阶段未能命名的项目，与在两个阶段都正确命名的项目（从而为一般的认知衰退提供对照）。在每个阶段，使用对口语化物体名称的定义来研究命名测试中图片所代表概念的语义知识，特别针对患者提供的感官和联想/功能特征的数量进行评分。在第二阶段，对已命名→未命名项目与已命名→已命名物体的定义进行分析，结果显示感官和联想信息均有显著损失。然而，对自然类（动物和鸟类）与人工制品（家用物品、车辆等）的比较表明，类别与定义中所含信息类型之间存在显著的相互作用。具体而言，已命名→未命名组中人工制品的第二阶段定义显示联想/功能信息不成比例地损失，而患者未能根据图片说出的动物名称的定义在感官特征方面明显缺乏。这种模式支持了这样一种观点，即成功的命名依赖于关键语义特征的一个子集，这些特征在不同类别的语义知识中会有所不同。我们认为，这些发现最好用一种语义组织概念来解释，即加权重叠组织特征（WOOF），其中：（i）关于所有物体的知识由一个由单词和图片激活的中央分布式特征网络表示，但（ii）自然类和人工制品在有利于那些参与了解和体验不同类型物体的特征方面具有不同的权重。
