Linguistic structure across time: ERP responses to coordinated and uncoordinated noun phrases

Relatively little is known about how linguistic structure is neurally encoded. The current study examines a relatively subtle manipulation of syntactic and semantic structure: the difference between reading a list of two noun phrases (“sunlit ponds ### green umbrellas”) and their syntactic coordination (“sunlit ponds and green umbrellas”). In two ERP experiments, the presence of the coordinator resulted in an increased anterior negativity across the entire second noun phrase, even though coordination had no direct relevance for the memory recognition task. These findings demonstrate that structural connectedness exerts strong, ongoing differences in neural activity even when structured and unstructured materials are very tightly matched in sequence and content. These differences may reflect ongoing maintenance of structure in memory, or computation of the more complex semantic or discourse representation associated with syntactic coordination.