Pylkkänen Liina, Llinás Rodolfo, Murphy Gregory L
Department of Linguistics, New York University, New York, NY 10003, USA.
J Cogn Neurosci. 2006 Jan;18(1):97-109. doi: 10.1162/089892906775250003.
Most words in natural language are polysemous, that is, they can be used in more than one way. For example, paper can be used to refer to a substance made out of wood pulp or to a daily publication printed on that substance. Although virtually every sentence contains polysemy, there is little agreement as to how polysemy is represented in the mental lexicon. Do different uses of polysemous words involve access to a single representation or do our minds store distinct representations for each different sense? Here we investigated priming between senses with a combination of behavioral and magnetoencephalographic measures in order to test whether different senses of the same word involve identity or mere formal and semantic similarity. Our results show that polysemy effects are clearly distinct from similarity effects bilaterally. In the left hemisphere, sense-relatedness elicited shorter latencies of the M350 source, which has been hypothesized to index lexical activation. Concurrent activity in the right hemisphere, on the other hand, peaked later for sense-related than for unrelated target stimuli, suggesting competition between related senses. The obtained pattern of results supports models in which the representation of polysemy involves both representational identity and difference: Related senses connect to same abstract lexical representation, but are distinctly listed within that representation.
自然语言中的大多数单词都是多义词，也就是说，它们可以有不止一种用法。例如，“paper”可以用来指由木浆制成的物质，也可以指印在这种物质上的日报。尽管几乎每个句子都有多义现象，但对于多义现象在心理词典中是如何表示的，人们几乎没有达成共识。多义词的不同用法是涉及对单一表征的访问，还是我们的大脑为每种不同的意义存储了不同的表征？在这里，我们结合行为和脑磁图测量方法研究了不同意义之间的启动效应，以测试同一个单词的不同意义是涉及同一性还是仅仅涉及形式和语义上的相似性。我们的结果表明，多义效应在双侧明显不同于相似性效应。在左半球，意义相关性引发了M350源的潜伏期缩短，据推测M350源可索引词汇激活。另一方面，右半球的并发活动在与意义相关的目标刺激上比在不相关的目标刺激上达到峰值的时间更晚，这表明相关意义之间存在竞争。所获得的结果模式支持了这样的模型，即多义现象的表征既涉及表征同一性又涉及差异性：相关意义连接到相同的抽象词汇表征，但在该表征中被明确列出。
