The recruitment of knowledge regarding plurality and compound formation during language comprehension.

Compound formation has been a major focus of research and debate in mental lexicon research. In particular, it has been widely observed that compounds with a regular plural non-head are dispreferred, and a long line of research has examined the nature of this constraint, including which morphological, semantic or phonological properties of the non-head underlie this dispreference. While it is typically assumed that this constraint in fact leads to the barring of a compound analysis to a noun-noun string which would otherwise violate the constraint, its implementation during sentence comprehension has not been thoroughly examined. Using self-paced reading, we demonstrate that knowledge of pluralization and compound formation is immediately utilized in the assignment of structure to noun-noun strings, and that the dispreference for regular plural non-heads in fact leads the parser away from the compound analysis in favor of a more complex grammatical alternative. These results provide new evidence for the online deployment of knowledge regarding pluralization and its interaction with compound formation, and inform our understanding of how morphological information is deployed during, and impacts real-time sentence comprehension.