Beretta Alan, Fiorentino Robert, Poeppel David
Department of Linguistics, Michigan State University, A-628 Wells Hall, East Lansing, MI 48824, USA.
Brain Res Cogn Brain Res. 2005 Jun;24(1):57-65. doi: 10.1016/j.cogbrainres.2004.12.006.
We examined the neural correlates of semantic ambiguity by measuring changes in MEG recordings during a visual lexical decision task in which the properties of ambiguous words were manipulated. Words that are ambiguous between unrelated meanings (like bark, which can refer to a tree or to a dog) were accessed more slowly than words that have no unrelated meanings (such as cage). In addition, words that have many related senses (e.g., belt, which can be an article of clothing or, closely related in sense, a fan belt used in machinery) were accessed faster than words that have few related senses (e.g., ant). The findings are inconsistent with accounts that posit that both kinds of ambiguity involve separate lexical entries, but instead offer both behavioral and neurophysiological support for separate entry accounts only for homonymy, and a single-entry model of polysemy. The findings also provide neural correlates for a behavioral study of lexical ambiguity that demonstrated that the frequently reported ambiguity advantage in lexical decision tasks is not due to the presence of many unrelated meanings but to the presence of many related senses.
我们通过在视觉词汇判定任务中测量脑磁图（MEG）记录的变化，来研究语义模糊性的神经关联，在该任务中对模糊词的属性进行了操控。在不相关意义之间存在模糊性的词（如“bark”，既可以指树，也可以指狗）的处理速度比没有不相关意义的词（如“cage”）更慢。此外，具有许多相关意义的词（例如“belt”，既可以是一件衣物，在意义上与机械中使用的风扇皮带密切相关）的处理速度比具有较少相关意义的词（例如“ant”）更快。这些发现与那种认为两种模糊性都涉及单独词汇项的观点不一致，而是仅为同音异义词的单独词条观点以及一词多义的单词条模型提供了行为和神经生理学支持。这些发现还为词汇模糊性的行为研究提供了神经关联，该研究表明，在词汇判定任务中经常报道的模糊性优势并非由于存在许多不相关意义，而是由于存在许多相关意义。
