Research on processing in English has shown that verb information facilitates predictive processing. Because Japanese verbs occur at the ends of clauses, this information cannot be used to predict the roles of preceding nominals. Kamide, Altmann and Haywood (2003) showed that native Japanese speakers use case markers to predict forthcoming linguistic items. In the present study, we investigated whether second language learners of Japanese demonstrate such predictive effects when processing sentences containing either the monotransitive or ditransitive constructions. A visual-world paradigm experiment showed that, although native speakers generated predictions for syntactic outcomes, the learners did not. These findings underscore the usefulness of morphosyntactic information in processing Japanese and indicate that learners fail to make full use of case markers to generate expectations regarding syntactic outcomes during online processing. Learners may rely on nonlinguistic information to compensate for this deficit in syntactic processing.

This study used self-paced reading to examine the processing of Japanese ditransitive scrambling by native speakers and second language (L2) learners of Japanese. Because Japanese places the verb at the end of the clause, the impact of verb-based expectations should be less than it is in English (Trueswell, Tanenhaus & Kello, 1993). Instead of using verb-driven processing, Japanese relies on case markers, and structure-building decisions are made locally (Miyamoto, 2002). As a result, if learners are able to utilize the information encoded by case markers, there should not be any extra processing load involved in scrambled sentences. Fifteen native speakers, 16 first language (L1) Korean intermediate-level learners, and 16 L1 English intermediate-level learners participated in the study. The conditions included canonical order, accusative scramble order, dative scramble order and dative-accusative scramble order. The results demonstrated that there are no significant differences in reading times among word-order types. These findings indicate that (1) Japanese native speakers make use of case-marked arguments as reliable cues for incremental processing, and (2) L2 learners can acquire this processing strategy at native-like levels, regardless of their L1 backgrounds.

This study examined whether native Japanese speakers and second language (L2) speakers of Japanese use information from numeral classifiers to predict possible referents. Using a visual-world eye-tracking paradigm, we asked participants to identify picture objects that take either the same or different numeral classifiers while they listened to Japanese sentences referring to one object. The results showed that native speakers looked to the target predictively more often when the classifier was informative about noun identity than when it was not. L2 learners also showed a facilitative effect of classifiers that was comparable to that of native speakers. In addition, we found that the level of proficiency played a role in the speed of real-time referent resolutions when the participants heard the target nouns in audio input. However, such an effect was not observed during the period when the predictions were generated.

Psycholinguistic research has shown that sentence processing is incremental (e.g., Altmann & Kamide, 1999). In Japanese, a verb-final language, native speakers use case markers to incrementally assign thematic roles and predictively activate a structural representation of upcoming linguistic items. This study examined whether second-language learners of Japanese, guided by case markers, generate predictions as to whether the upcoming verb involves the active or passive voice. The results show that the native speakers made predictive eye movements before the verb, but the learners did not; the learners were less efficient in using case-marker cues than the native speakers and relied more on verb morphology information. These results suggest that case markers guide thematic role assignments, expediting the processing for Japanese native speakers. Learners may depend more on information from the verb to compensate for the inefficiency in case-marker-driven predictive processing.

This study examines whether second language (L2) learners predict upcoming language prior to the verb in Japanese. Taking the dependency involving negative polarity adverbs – zenzen ‘at all’ and amari ‘(not) very’ – as a test case, this study examined whether Japanese native speakers and L2 learners of Japanese, aided by these adverbs, generate predictions of the polarity of the sentence-final verb. The visual-world paradigm experiment revealed that both native-speaker and L2-learner groups looked progressively more at the target picture before the negated verb when the information from adverbs was available than when it was not. The pattern of results underscores the usefulness of adverbial polarity items as predictive cues and indicates that they expedite the processing of negation in Japanese. Learners successfully exploited this information to generate nativelike predictions on sentence meaning.