Differential Object Marking in Structurally Complex Contexts in Spanish: Evidence from Bilingual and Monolingual Processing

This study examines whether Differential Object Marking (DOM) realization and word order in relative clauses (RCs) in Spanish affect processing and interpretation among monolinguals and highly proficient Catalan–Spanish bilinguals. RCs are parallel in Catalan and Spanish, but DOM is much more restricted in Catalan than in Spanish, and, interestingly, the distinction between subject and object RCs relies mainly on the presence/absence of DOM. To examine DOM optionality, we concentrate on the top portion of the animacy scale and test the human/non-human contrast. Exploring these two populations allows us to test whether they resort to different strategies for the following three reasons: (1) bilingualism places an increased burden on memory processes); (2) the partial overlap between both DOM systems might lead to the influence from Catalan into Spanish); and (3) optionality has been proposed to characterize bilingual grammars). Findings from a word-by-word non-cumulative self-paced reading task showed that DOM modulates RC processing. With [+human] obligatorily marked objects, both monolinguals and bilinguals read subject RCs faster than object RCs, suggesting a strategy favoring subject RCs. However, monolinguals solved the interpretation early while processing but bilinguals, despite the more restricted DOM character of Catalan, are sensitive to DOM albeit displaying delayed spill-over effects. With [−human] optionally marked objects, bilinguals performed faster than monolinguals. We suggest that the uneven experience with DOM in Catalan, particularly with the non-standard variety that frequently displays DOM and that our bilinguals also speak in everyday conversations, facilitates bilinguals’ adaptation to the optional marking of non-human objects in Spanish, much in the same manner that they accommodate the presence or absence of DOM with both human and non-human objects in other native language.