Grewe Tanja, Bornkessel Ina, Zysset Stefan, Wiese Richard, von Cramon D Yves, Schlesewsky Matthias
Research Group Neurolinguistics, Philipps University, Marburg, Germany.
Hum Brain Mapp. 2005 Nov;26(3):178-90. doi: 10.1002/hbm.20154.
A number of neuroimaging studies have implicated an involvement of Broca's area, particularly of the pars opercularis of the left inferior frontal gyrus (IFG), in the processing of complex (permuted) sentences. However, functional interpretations of this region's role range from very general (e.g., in terms of working memory) to highly specific (e.g., as supporting particular types of syntactic operations). A dissociation of these competing accounts is often impossible because in most cases, the language internal complexity of permuted sentence structures is accompanied invariably by increasing costs of a more general cognitive nature (e.g., working memory, task difficulty, and acceptability). We used functional magnetic resonance imaging to explore the precise nature of the pars opercularis activation in the processing of permuted sentences by examining the permutation of pronouns in German. Although clearly involving a permutation operation, sentences with an initial object pronoun behave like simple, subject-initial sentences (e.g., in terms of acceptability) because of a rule stating that pronouns should generally precede non-pro-nominal arguments. The results of the experiment show that in contrast to non-pro-nominal permutations, sentences with a permuted pronoun do not engender enhanced pars opercularis activation. Our findings therefore speak against both language-related working memory and transformation-based accounts of this region's role in sentence comprehension. Rather, we argue that the pars opercularis of the left IFG supports the language-specific linearization of hierarchical linguistic dependencies.
多项神经影像学研究表明，布洛卡区，尤其是左额下回（IFG）的岛盖部，参与了复杂（置换）句子的处理。然而，对该区域作用的功能解释范围很广，从非常笼统的（例如，就工作记忆而言）到高度具体的（例如，作为支持特定类型的句法操作）。由于在大多数情况下，置换句子结构的语言内部复杂性总是伴随着更一般认知性质（例如，工作记忆、任务难度和可接受性）成本的增加，所以往往无法区分这些相互竞争的解释。我们使用功能磁共振成像来研究德语中代词置换时，岛盖部在处理置换句子时激活的精确性质。尽管明显涉及置换操作，但由于一条规则规定代词通常应位于非代词性成分之前，所以以宾语代词开头的句子在表现上（例如，就可接受性而言）类似于简单的、以主语开头的句子。实验结果表明，与非代词性置换不同，代词置换的句子不会引起岛盖部激活增强。因此，我们的研究结果反对该区域在句子理解中与语言相关的工作记忆和基于转换的解释。相反，我们认为左IFG的岛盖部支持层次语言依存关系的特定语言线性化。
