Using a second language learned in adulthood efficiently and fluently is a formidable task. This project investigates how the processing of a second language by adult learners differs from the processing of a native language. The questions addressed by this research are (i) whether adult second language learners make use of different types of linguistic information, such as word order and animacy cues, in the same way as native speakers; and (ii) how individual differences in working memory capacity affect the use of each type of information in the processing of a native vs. a second language.
Under the direction of Tania Ionin and with support from the National Science Foundation, Ms. Soondo Baek will investigate the processing of English relative clauses by native speakers and adult second language learners of English. Previous research shows that object relative clauses (e.g., the reporter who the senator attacked) are harder to interpret than subject relative clauses (e.g., the reporter who attacked the senator). It has also been shown that lexical-semantic properties of nouns modulate the degree of processing difficulty of the two types of relative clauses. For example, object relative clauses with an inanimate head noun and an animate relative clause subject (e.g., the movie that the director watched) are no more difficult to process than corresponding subject relative clauses, whereas those with an animate head noun and an inanimate relative clause subject (e.g., the director that the movie pleased) are harder to process than subject relative clauses.
This project tests whether adult second language learners are sensitive both to syntactic complexity, as represented by the subject-object asymmetry in relative clauses, and to lexical-semantic information, as represented by the animacy of the relevant nouns. Furthermore, this project examines how individual learners of different working memory capacity and different L2 proficiency differ from one another in the degree of sensitivity to these two types of information. The results will contribute to a better understanding of (i) sentence processing mechanisms employed for a native language and for a second language learned in adulthood and (ii) the factors responsible for the wide range of individual variability in the processing of a second language by adult learners. The results of this research also have potential pedagogical implications for second language teaching, through its attention to individual learner differences in language processing.
Adults learn one or more additional languages other than their native language for various reasons. It is a very challenging task for most of them to reach a proficiency level at which they can use the non-native language as fluently as the native speakers of the language. Much of the research work on acquisition and use of a second language (L2) has focused on possible causes for the difficulty adults experience in learning and using a L2. The project aimed to further our understanding of the sources of this difficulty by examining how adults comprehend L2 sentences as compared to native speakers of the language. Some researchers suggest that adults use basically the same cognitive systems to comprehend L1 and L2 sentences, and attribute their increased difficulty with L2 sentences to the reduced processing capacity resulting from the lack of sufficient experience and practice with the language. This view thus highlights quantitative differences between L1 and L2 sentence comprehension. Other researchers, on the other hand, propose that most of the difficulty adult L2 learners experience is associated with analyzing the formal structure of a L2 sentence they read, while they are good at inferring the meaning of the sentence based on the meaning of individual words and their world knowledge. The latter view further proposes that the increased difficulty adults experience with formal aspects of a L2 is due to some maturational change in the cognitive system that is responsible for the acquisition and use of language. The project tested the two opposing views on the differences between L1 and L2 sentence comprehension through a series of experiments, in which adult native speakers and Korean-speaking learners of English read English sentences manipulated in terms of structural and semantic complexity. The time taken to read these sentences was measured word by word to investigate how sensitive the participants were to structural vs. semantic aspects of the sentences. The results showed that the L2 learners were sensitive to both syntactic and semantic complexity in a comparable pattern to that shown by the native English speakers. Any difference between the two groups of participants appeared only when the experimental sentences became very complex due to a conflict between the structure and meaning of the sentences. Furthermore, the difference was due to the L2 learners’ reduced ability to take into account semantic information as compared to structural information. These results suggest that the processing difficulty involved with L2 sentence comprehension should be attributed to the generally reduced processing capacity or efficiency of L2 learners, rather than to some maturational change in the language faculty that is often associated with a specific deficit in the ability to learn the formal aspects of language. These findings are thus more consistent with the quantitative view of L1-L2 differences in sentence comprehension.
