The Cognitive And Neural Mechanism Of The Language Switch In Chinese-English Bilinguals

Bilinguals will face the problem of language switch when they process the language. The paper researches into the cognitive and neural mechanism of the language switch of bilinguals as follows: (1) word association test of L1 and L2 mental lexicon; (2) neighborhood effect test of the bilinguals; (3) MSIT with Stroop, Simon and Flanker combined; (4) behavioral experiment of the even-odd number language switch; (5) ERP experiment of the even-odd number language switch. The results give us the following implications: (1) The word association test based on L2 mental lexicon explores the semantic relation of the words. Most of the responses of the L2 learners are semantically-related including paradigmatic relation, syntagmatic relation, clang response null response in the order of importance, showing that semantics plays an important role in the construction of the L2 mental lexicon. (2) More proficient L2 learners perform better in finishing neighborhood word decision task without sex differences. Neighborhood density and frequency facilitate the English word recognition, similar to the result of the alphabetic language. (3) The proficiency of the L2 learners is positively related to the ability to resolve the conflicts. Although English majors do not pose advantage in the accuracy and reaction times, English majors do much better than non-English majors in the middle position of the interference trials, the most difficult position in the test. (4) Language switch cost is an essential factor in finishing the Language switch task. When switching from L1 to L2, more proficient L2 learners perform faster. When switching from L2 to L1, less proficient spend more time. As to the within-language switch, more proficient L2 learners perform much better than less proficient L2 learners, indicating more proficient L2 learners develop high sensitivity than less proficient L2 learners. English-Chinese switch and Chinese-English switch are different at 150ms-180ms(N150)and 240ms-260ms(P300)with the biggest difference at 500-600ms. At N150 component the bigger amplitude can be seen in English-Chinese switch than Chinese-English switch without obvious early latency in the middle and posterior brain, demonstrating that when Chinese native speakers switch from L2 to L1, the top-down interference is needed, that is, the influence of the frontal lobe and parietal lobe. To conclude, the language switch from L1 to L2, and from L2 to L1 assumes a different pattern.