Parsing Effects in Second Language Sentence Processing

This paper reexamines claims that second language learners are more accurate at judging long-distance object extraction than subject extraction and that the difference in accuracy is due to processing factors rather than differences in underlying competence. Although previous studies have reported robust effects for the subject/object asymmetry, the global nature of the response measures leaves open the question of whether the subject gap is in fact the locus of difficulty for second language learners. Using many of the same stimuli sentences from original research in combination with a theory of principle-based parsing, this study employs the moving window display technique to collect on-line measures of processing long-distance wh -extraction. Twenty-five advanced Chinese-speaking ESL learners provided grammaticality judgments in two presentation conditions: full-sentence, where judgment reaction times are measured from sentence onset to the learner's judgment; and word-by-word reading, where word-by-word latencies are collected in addition to judgments. The accuracy and reaction time results from the full-sentence condition replicated previous findings. The word-by-word results confirm that it is the subject gap that is the source of difficulty for the learners. Claims in the literature that principles of Universal Grammar are not available to adult learners are not supported by these results, which show that parsing, and not grammatical competence, is the source of difficulty on performance with subject extraction sentences.