It depends: Optionality in the production of filler-gap dependencies

This study investigates the language production mechanisms underlying the creation of filler-gap dependencies (e.g., relative clauses: This is the boy that the girl from Norway saw_ yesterday), which require speakers to establish an argument-predicate relationship between a phrase, the ‘filler’ (the boy) and a further embedded predicate (saw). We show that filler-gap dependency production involves the retention of a representation of the filler until the relevant embedded position. We then report three elicitation experiments examining how English and Hebrew speakers manage and moderate filler retention demands via production choices. In Experiments 1 (English) and 2 (Hebrew), speakers produced restrictive relative clauses and non-restrictive relative clauses with the latter predicted to impede filler retention. In Experiment 3 (Hebrew), speakers produced relative clauses with and without intervening material creating interference for filler retention. We found that English speakers use passivization to moderate filler-retention demands via the creation of shorter dependencies. In Hebrew, impeded filler retention resulted in increased rate of grammatical resumption. We conclude that the production of filler-gap dependencies invokes cognitive strategies that manage the memory burdens that they impose.