Prediction in bilingual sentence processing

The Unified Competition Model (MacWhinney, 2012) accounts for cross-linguistic differences in thematic role mapping. We investigated production and predictive use of accusative case morphology in Russian-Hebrew bilingual children. We also investigated the role of production in predictive processing testing the Prediction-by-Production Account (Pickering & Garrod, 2018) vs. the Missing Surface Inflection Hypothesis (Prévost & White, 2000). Three groups of children aged 4–8 participated: Russian-Hebrew-speaking bilinguals, Russian-speaking and Hebrew-speaking monolingual controls. All children participated in the accusative case production and Visual-World eye-tracking comprehension experiments. Bilinguals were tested in both of their languages. The results of the study confirmed the predictions of the Unified Competition Model showing typological differences in the strength of the case-marking cue and its predictive use in sentence processing in Russian- and Hebrew-speaking controls. While Russian-speaking monolinguals relied on case marking to predict the upcoming agent/patient, the performance of Hebrew-speaking monolingual children varied. The findings for bilinguals showed that despite their lower production accuracy in both languages, they were either indistinguishable from monolinguals or showed an advantage in the predictive use of case morphology. The findings support the Missing Surface Inflection Hypothesis, which predicts a dissociation between production and comprehension.