Nieuwland Mante S, Petersson Karl Magnus, Van Berkum Jos J A
Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands.
Neuroimage. 2007 Sep 1;37(3):993-1004. doi: 10.1016/j.neuroimage.2007.05.048. Epub 2007 Jun 7.
In an event-related fMRI study, we examined the cortical networks involved in establishing reference during language comprehension. We compared BOLD responses to sentences containing referentially ambiguous pronouns (e.g., "Ronald told Frank that he..."), referentially failing pronouns (e.g., "Rose told Emily that he...") or coherent pronouns. Referential ambiguity selectively recruited medial prefrontal regions, suggesting that readers engaged in problem-solving to select a unique referent from the discourse model. Referential failure elicited activation increases in brain regions associated with morpho-syntactic processing, and, for those readers who took failing pronouns to refer to unmentioned entities, additional regions associated with elaborative inferencing were observed. The networks activated by these two referential problems did not overlap with the network activated by a standard semantic anomaly. Instead, we observed a double dissociation, in that the systems activated by semantic anomaly are deactivated by referential ambiguity, and vice versa. This inverse coupling may reflect the dynamic recruitment of semantic and episodic processing to resolve semantically or referentially problematic situations. More generally, our findings suggest that neurocognitive accounts of language comprehension need to address not just how we parse a sentence and combine individual word meanings, but also how we determine who's who and what's what during language comprehension.
在一项与事件相关的功能磁共振成像研究中，我们研究了语言理解过程中建立指代关系所涉及的皮层网络。我们比较了对包含指代模糊代词（例如，“罗纳德告诉弗兰克他……”）、指代失败代词（例如，“罗斯告诉艾米丽他……”）或连贯代词的句子的血氧水平依赖（BOLD）反应。指代模糊选择性地激活了内侧前额叶区域，这表明读者在进行问题解决，以便从话语模型中选择一个唯一的指代对象。指代失败引发了与形态句法处理相关的脑区激活增加，并且，对于那些将失败代词理解为指代未提及实体的读者，还观察到了与精细推理相关的额外脑区激活。由这两种指代问题激活的网络与由标准语义异常激活的网络并不重叠。相反，我们观察到一种双重分离，即由语义异常激活的系统在指代模糊时被去激活，反之亦然。这种反向耦合可能反映了为解决语义或指代问题情境而对语义和情景处理的动态调用。更一般地说，我们的研究结果表明，语言理解的神经认知解释不仅需要解决我们如何解析句子并组合单个单词的含义，还需要解决我们在语言理解过程中如何确定人物和事物的问题。
