Neuroscience and Aphasia Research Unit, School of Psychological Sciences, University of Manchester, Manchester M13 9PL, United Kingdom. matt.lambon-ralph@manchester
Proc Natl Acad Sci U S A. 2010 Feb 9;107(6):2717-22. doi: 10.1073/pnas.0907307107. Epub 2010 Jan 21.
In his Philosophical Investigations, Wittgenstein famously noted that the formation of semantic representations requires more than a simple combination of verbal and nonverbal features to generate conceptually based similarities and differences. Classical and contemporary neuroscience has tended to focus upon how different neocortical regions contribute to conceptualization through the summation of modality-specific information. The additional yet critical step of computing coherent concepts has received little attention. Some computational models of semantic memory are able to generate such concepts by the addition of modality-invariant information coded in a multidimensional semantic space. By studying patients with semantic dementia, we demonstrate that this aspect of semantic memory becomes compromised following atrophy of the anterior temporal lobes and, as a result, the patients become increasingly influenced by superficial rather than conceptual similarities.
在他的《哲学研究》中，维特根斯坦著名地指出，语义表示的形成需要的不仅仅是言语和非言语特征的简单组合，以生成基于概念的相似性和差异性。经典和当代神经科学往往侧重于不同的新皮层区域如何通过对特定模态信息的总和来促进概念化。计算连贯概念的额外但关键的步骤却很少受到关注。一些语义记忆的计算模型能够通过添加在多维语义空间中编码的模态不变信息来生成这样的概念。通过研究语义性痴呆患者，我们证明了语义记忆的这一方面在颞叶前部萎缩后会受到影响，因此患者会越来越受到表面相似性而不是概念相似性的影响。
