The Effect Of Context Videos On EFL Listening Comprehension In CALL Environment

With the rapid advance of modern technology, multimedia has been widely applied in the course of language teaching and learning. In recent years, the effect of visuals on foreign language listening has attracted lots of attention, and many researchers have drawn positive conclusions from macro perspectives, but these findings lack systematically theoretical background. Bejar, et al divided visuals into context visuals and content visuals in 2000, but they had not further classified them elaboratively, so studies on visuals suspended at this level. Thus, based on dual-coding theory, cognitive load theory and cognitive theory of multimedia learning, the present research employs a combination of qualitative and quantitative approach to investigate the effect of contextual elements of English videos on EFL learners'listening comprehension. To accomplish this aim, the study mainly checks: (1) The classification of the contextual elements and their multimodal effect in English video listening comprehension; (2) The effect of different kinds of context videos on EFL listening comprehension; (3) Participants'attitudes towards different context videos and the correspondence between their attitudes and their performance.Based on the classification of visuals (Bejar, et al, 2000) and the variables about context proposed by Hymes (1977), the researcher contrives to classify context videos into three kinds, namely, strong context video: videos offer specific, relative setting and participants, clear end and definite act sequence; weak context video: videos offer specific, relative setting and either participants or not, clear end but indefinite act sequence; and zero context video: videos offer irrelevant setting and participants or no setting and participants, clear end but indefinite act sequence.The subjects of the present research are fifty English-major sophomores. Altogether, there are four listening materials used in the experiment, namely, a strong context video, a weak context video, a zero context video and an audio, and all the three videos have no captioning. The test is conducted in a language lab and each material is played once only. When the test is finished, ten subjects have been selected randomly to attend the post-test interview to explore their attitudes towards different kinds of context videos and the feasibility of application of context videos in listening classroom.Findings of the present study show that the multimodal effect of context videos depends on the amount of contextual information they presented, while not all the context videos have positive multimodal effect. That's to say, compared with the audio, both strong context video and weak context video can improve EFL learners'listening comprehension, which echoes the results of previous studies. It is also found that zero context video impedes learners'performance. For this issue one possible explanation is that only extremely limited and topic-irrelevant contextual visual information is provided in zero context video, while learners have to distribute their limited working memory to both visual and auditory channels, which results in split–attention effect. What's more, there are statistically significant differences among the effect of three kinds of context videos on EFL learners'listening comprehension. To be specific, compared with zero context video, both strong context video and weak context video have significantly better influence on EFL learners'listening comprehension. The cause for this distinctness might be both strong and weak context videos, in comparison to zero context video, provide more contextual visual information so that subjects can make reasonable inference about the content of materials. What's more, subjects employ dual channels while taking the test, the verbal explanation and visual presentation can interact with each other to strengthen listening comprehension. While zero context video carries restricted contextual visual presentation, the dual channels can't reinforce each other, which lead to redundant effect. Finally, the results of post-test interview show that strong context video is the most preferred one, followed by weak context video, while zero context video is the least favored. Interviewees'attitudes towards different context videos are in accord with their performance on listening comprehension test. Therefore, the results of present study throw light on how to better the design of English audio-visual instruction. Meanwhile, they can also benefit EFL learners to a certain degree as for how to select suitable videos to improve their listening.