Effects Of Working Memory Capacity And Lnput Modes On Incidental Lexical Chunk Acquisition

More and more scholars have focused on incidental lexical chunk acquisition recently.However,there are a fewer studies concerning incidental lexical chunk acquisition than incidental vocabulary acquisition.Visual input and aural input play an important role in second language learning.Most studies concerning input modes have focused on vocabulary learning and text comprehension while less attention has been paid to the acquisition of lexical chunks.Previous studies have found that working memory capacity and input modes have some influence on vocabulary acquisition,but only involved the effects of only one of the two factors on lexical chunk acquisition.Based on input hypothesis,working memory and cognitive load theory,the present study is designed to explore the effects of working memory capacity and three input modes(visual before aural input,simultaneous visual and aural input and aural before visual input)on incidental lexical chunk acquisition.Eighty two students took part in the working memory test.Then according to their scores,sixty three students were chosen and divided into high working memory capacity(high-WM)group and low working memory capacity group(low-WM).High-WM group included 29 participants and low-WM group included 34 participants.Three experimental groups were formed by selecting students from each WM group respectively and randomly.Then participants in three experimental groups were exposed to three types of presentation of visual and aural input respectively:visual-before-aural input(VBA),simultaneous visual and aural input(V+A)and aural-before-visual input(ABV).Later,an immediate lexical chunk posttest and a delayed posttest after one week were conducted.The present study adopted SPSS 22.0 to analyze data and concluded the following results.First,working memory capacity has a significant impact on incidental lexical chunk acquisition.High-WM participants outperform low-WM participants in the immediate and delayed posttest.Second,different input modes have different impacts on lexical chunk acquisition.V+A group performs significantly better than ABV group.But there is no significant difference between VBA group and ABV group.There are the same findings in the delayed posttest.Third,there are interactive effects of working memory capacity and input modes on incidental lexical chunk acquisition in both immediate and delayed posttest.High-WM participants perform best in V+A group while low-WM participants perform worst.To sum up,incidental lexical chunk acquisition is influenced by working memory capacity and input modes.This study confirms input hypothesis,working memory theory and cognitive load theory,which has some implications for lexical chunk teaching.First,teachers can promote incidental acquisition of lexical chunks through reading and listening exercises.Besides,teachers should adopt the proper input mode for L2 learners with different working memory capacity.