An Empirical Study On The Effects Of Key Visuals And Working Memory Capacity On The English Listening Comprehension Of High School Students

L2 listening comprehension,as one of the most important skills of second language acquisition,has attracted more and more attention of language researchers.Numerous studies have been conducted to investigate the effects of working memory capacity on L2 listening comprehension;whereas little research has been conducted on the relationship between working memory and key visuals.Thus,this study aims to discuss the effects of the working memory capacity and key visuals on L2 learners' listening comprehension.To be more specific,it deals with the following research questions:1.Is there any significant effect of key visuals on high school students' listening comprehension?2.Is there any significant effect of working memory capacity on high school students' listening comprehension?3.Does the effect of key visuals on high school students' listening comprehension vary according to working memory capacity?To answer these questions,a 2(key visuals)×3(working memory capacity)two-way ANOVA design was used in the present study.The 90 subjects,whose language proficiency was at the same level,were from three intact classes of high school in China.The subjects were divided into three groups according to their performance in working memory test,which were low working memory capacity,medium working memory capacity group and high working memory capacity group.It was measured from two aspects:information processing and information storage by a computerized listening span test(LST)that was adapted from the version designed by Daneman and Carpenter(2009).The subjects were divided into two groups,i.e.,the group provided with key visuals and the group without the presence of key visuals.Students' English listening comprehension was measured according to their performance in the English listening comprehension tests.The passages of the listening comprehension tests were chosen from the previous IELTS examinations.Recall protocol test and sentence verification test were employed to measure the English listening comprehension level.Some two-way ANOVA were conducted to analyze the data in the study.The major findings are presented as follows:1.Key visuals have a significant effect on L2 learners'listening comprehension.The results also show that the three working memory capacity groups have improved with the aid of key visuals on listening comprehension.In addition,low working memory capacity group makes more progress than medium working memory capacity group and high working memory capacity group.2.Working memory capacity has a significant effect on L2 learners'listening comprehension in terms of both recall protocol test and sentence verification test.The results indicate that L2 learners with high working memory capacity perform better in recall protocol test and SVT than those with low working memory capacity and medium working memory.3.There is a significant interaction effect between working memory capacity and key visuals on L2 learners'listening comprehension in terms of sentence verification test.However,there is no significant interaction effect in terms of recall protocol test.These results imply that the background knowledge provided by the key visuals inhibits the role of working memory capacity in L2 listening performance.The participants with low working memory capacity can make better use of the key visuals than those with higher working memory capacity to improve their performance in the sentence verification task.To sum up,high school students' listening comprehension is significantly affected by key visuals and working memory capacity.What's more,key visuals can help reduce the working memory load in L2 listening comprehension.These results also support working memory capacity theory and schema theory.furthermore,some important pedagogical implications are summarized as:though working memory capacity cannot be manipulated or changed,teachers can employ some techniques and invent some teaching programs,such as key visuals to reduce the students' working memory capacity burden and make up for the limitations of working memory capacity.