This study tests whether prediction error underlies structural priming in a later-learnt L2 across two visual world eye-tracking priming experiments. Experiment 1 investigates priming when learners encounter verbs biased to double-object-datives (DO, “pay”) or prepositional-object-datives (PO, “send”) in the other structure in prime sentences. L1-German–L2-English learners read prime sentences crossing verb bias and structure (DO/PO). Subsequently, they heard target sentences – with unbiased verbs (“show”) – while viewing visual scenes. In line with implicit learning models, gaze data revealed priming and prediction-error effects, namely, more predictive looks consistent with PO following PO primes with DO-bias verbs. Priming in comprehension persisted into (unprimed) production, indicating that priming by prediction error leads to longer-term learning. Experiment 2 investigates the effects of target verb bias on error-based priming. Priming and prediction-error effects were reduced for targets with non-alternating verbs (“donate”) that only allow PO structures, suggesting learners’ knowledge of the L2 grammar modulates prediction-error-based priming.

This study investigates whether cross-linguistic differences affect how adult second language (L2) learners use different types of verb subcategorization information for prediction in real-time sentence comprehension. Using visual world eye-tracking, we tested if first language (L1) German and L1 Turkish intermediate-to-advanced learners of L2 English make use of categorical and gradient probabilistic selectional information of ditransitive verbs to predict whether the verbs would be followed by prepositional-object or double-object dative constructions. L1 German learners used both categorical (“pay/*donate the woman the money”) and gradient (“pay/#send the woman the money”) constraints for prediction in a target-like manner. In contrast, L1 Turkish learners were delayed in recruiting categorical verb information and were only selectively sensitive to gradient verb information. We argue that target-like predictive processing across categorical and gradient verb information is attainable for L2 learners, but differences in L1-L2 word order may curtail the utility of prediction by verb subcategorization information in L2 processing.