Fiebach Christian J, Ricker Brigitte, Friederici Angela D, Jacobs Arthur M
Departments of Psychology and Neurology, Ruprecht-Karls-Universität Heidelberg, Germany.
Neuroimage. 2007 Jul 1;36(3):901-11. doi: 10.1016/j.neuroimage.2007.04.004. Epub 2007 Apr 12.
The recognition of words is a central component of language processing. A major role for visual word recognition has been attributed to the orthographic neighbors of a word, i.e., words that are orthographically similar to a target word. It has been demonstrated that the presence of orthographic neighbors facilitates the recognition of words, but hinders the rejection of nonwords. It is therefore assumed that representations of orthographic neighbors are at least partially activated during word recognition, and that they influence word recognition depending on the specific task context. In the present study, we used fMRI to examine the neural bases of the effect of orthographic neighborhood size on speeded lexical decisions to words and nonwords. Our results demonstrate lexicality x neighborhood size interactions in mid-dorsolateral and medial prefrontal cortex, suggesting the involvement of a domain-general, extra-lexical process for orthographic neighborhood effects on word and nonword processing. This result challenges computational models that offer purely lexical accounts of the orthographic neighborhood effect and suggests an important role for executive control functions during visual word recognition.
单词识别是语言处理的核心组成部分。视觉单词识别的一个主要作用归因于一个单词的正字法邻域，即与目标单词在正字法上相似的单词。已经证明，正字法邻域的存在有助于单词的识别，但会阻碍非单词的排除。因此可以假设，在单词识别过程中，正字法邻域的表征至少会部分被激活，并且它们会根据特定的任务背景影响单词识别。在本研究中，我们使用功能磁共振成像来检查正字法邻域大小对单词和非单词快速词汇判断影响的神经基础。我们的结果表明，在背外侧中部和内侧前额叶皮层存在词汇性×邻域大小的相互作用，这表明存在一个领域通用的、词汇外的过程参与正字法邻域对单词和非单词处理的影响。这一结果挑战了那些仅从词汇角度解释正字法邻域效应的计算模型，并表明执行控制功能在视觉单词识别过程中起着重要作用。
