On the processing of Japanese wh-questions: an ERP study.

The processing of Japanese wh-questions was investigated using event-related brain potentials (ERPs). Unlike in English or German, a wh-element in Japanese need not be displaced from its canonical position, but instead needs a corresponding Q(uestion)-particle to indicate its interrogative scope. We tested to see if there were any processing correlates specific to these features of Japanese wh-questions. Both mono-clausal and bi-clausal Japanese wh-questions elicited right-lateralized anterior negativity (RAN) between wh-words and corresponding Q-particles, relative to structurally-equivalent yes/no-question control conditions. These results suggest a reliable neural processing correlate of the dependency between wh-elements and Q-particles in Japanese, similar to effects of (left) anterior negativity between wh-fillers and gaps in English and German, but with a right- rather than left-lateralized distribution. It is suggested that wh-in-situ questions in Japanese are processed by the incremental formation of a long-distance dependency between wh-elements and their Q-particles, resulting in a working memory load for keeping track of scopeless wh-elements.

Event-related brain indices of Japanese scrambling.

This study examined the processing of Japanese wh-questions with preposed (scrambled) vs. in-situ (canonical SOV word order) wh-objects, and of yes/no-questions with scrambled vs. in-situ demonstrative objects. Questions with scrambled objects elicited bilateral slow anterior negative potentials between filler and gap. Scrambled demonstratives elicited P600 effects following the filler and (L)AN/P600 effects at the gap, while scrambled wh-words elicited primarily (L)AN effects at the gap. This replicated effects in response to filler-gap dependencies created by wh-movement in other languages, supporting the existence of universal parsing operations for all types of filler-gap dependencies. We suggest that these results are most generally compatible with notions of canonicity in sentence processing.