This study examined the brain areas involved in combining words into larger units when there are few or no morphosyntactic cues. We manipulated constituent length in word strings of the same length under two conditions: Mandarin sentence, which had sparse morphosyntactic cues, and nominal phrase that had no morphosyntactic cues [e.g., ((honey mustard) (chicken burger))]. Contrasting sentences to word lists revealed a network that largely overlapped with the one reported in languages with rich morphosyntactic cues, including left IFGorb/IFGtri and areas along left STG/STS. Both conditions showed increased activation in left IFGtri/IFGorb in functional ROIs defined based on previous study in sentence processing, while the nominal phrases additionally revealed a constituent length effect in bilateral dorsal IFGtri, left IFGoper, left pMTG/pSTG, left IPL, and several subcortical areas, which might reflect an increased reliance on semantic and pragmatic information. Moreover, in upper left IFGtri/IFGoper and left thalamus/caudate, this effect increased with the participants' tendency to combine nouns into phrases. The absence of syntactic constraints on linguistic composition might highlight individual differences in cognitive control, which helps to integrate non-syntactic information.

这项研究检查了在很少或没有形态句法提示时将单词组合成更大单位的大脑区域。我们在两个条件下操纵了相同长度的单词串中的组成长度：普通话句子（具有稀少的句法句法线索）和名词短语（没有（句法）“句法”句法线索[例如，（（蜂蜜芥末）（鸡肉汉堡）]））。句子与单词列表的对比显示出一个网络，该网络与具有丰富的句法线索的语言所报告的网络重叠，包括左IFGorb / IFGtri和左STG / STS区域。两种情况均显示了基于先前句子处理研究中定义的功能性ROI中左IFGtri / IFGorb的激活增加，而名词短语还显示了双侧背侧IFGtri，左IFGoper，左pMTG / pSTG的组成长度效应，离开IPL和几个皮质下区域，这可能反映出对语义和实用信息的依赖性增加。此外，在左上方的IFGtri / IFGoper和左丘脑/尾状中，随着参与者倾向于将名词组合成短语，这种效果会增加。语言组成上没有句法约束可能会突出认知控制中的个体差异，这有助于整合非语法信息。