Effects Of Encoding And Retrieval On L2 Discourse Comprehension

In recent years, many studies relating to encoding and retrieval have found that retrieval not only enhances learning, but also is superior to traditional repeated study method in memory retention, which is later proposed as ―Retrieval Practice Effect‖ or ―Testing Effect‖. Afterwards, researchers found that practicing retrieval even produces more learning than elaborative study with concept mapping in memory retention and knowledge transfer. However, this conclusion received both praise and criticism from other researchers. Retrieval practice effect has attracted more and more attention in the fields of cognitive psychology and education. It has been tested and verified in different acquisition fields, but the relevant studies in SLA are of great rarity. In order to discuss the function of retrieval in the field of SLA, the present study investigated learners‘ understanding of L2 discourse comprehension under different encoding and retrieval conditions from the perspective of information processing with learners‘ second language proficiency taken into consideration.The present study was developed around the following three research questions:1) Among encoding methods(repeated study and concept mapping) and retrieval method(free recall), which one is most beneficial to the immediate L2 discourse comprehension?2) Among encoding methods(repeated study and concept mapping) and retrieval method(free recall), which one is most beneficial to the retention of L2 discourse comprehension?3) Will the effects vary with learners‘ language proficiency?The participants in the present study were 108 non-English major freshmen from Wuxi City College of Vocational Technology. The three parallel classes were randomly assigned to repeated study group, concept mapping group and free recall group. No significant difference was found between groups. The testing material was an English passage containing 266 words, which conforms to participants‘ language proficiency. In the repeated study group, participants read the passage for four consecutive times, each time lasting 6mins. In the concept mapping group, participants were first instructed how to create a concept map of a certain passage to make sure that they grasped the method before the main experiment. In the final experiment, they read the passage for 6mins, and then began to create their own concept maps with the reference of the material for 18 mins. In the free recall group, participants first read the passage for 5mins, then recalled it and wrote it down on the paper without the reference of material for 7mins. After that, they read the passage for 5mins and recalled it again for 7mins as before. They were allowed to finish their recalling task either in English or in Chinese. The total amount of experiment time was 24 mins for all the groups. After learning period, participants took a final short-answer test of the learning material(two verbatim questions and one inference question). At last, questionnaire and interview were conducted to get to know participants‘ article-process course. One week later, all the participants took a delayed test that had the same content with the immediate test. Results were obtained after analyzing the statistical data:1) In the immediate test, participants in the free recall group has the best performance in L2 discourse comprehension both in the VQ test and the IQ test. According to the episodic context account, retrieval practice during study period can guide a search process and restrict search set by temporal context reinstatement, which will be helpful to its successful retrieval in the future. For VQ test, repeated study group outperforms concept mapping group, but it under-performs concept mapping group in the IQ test. This is mainly because creating a concept map requires participants to grasp the gist and general structure of a text, while repeated study tends to let participants pay more attention to the details of a text.2) In the delayed test, free recall is the most beneficial one to the memory retention of L2 discourse comprehension both in the VQ test and the IQ test, while concept mapping performs the worst. However, because of the difficulty of second language learning and the low language proficiency of participants, free recall group has a big decline from the immediate test to the delayed test. Due to the method complexity of concept mapping as well as the significant influence of learners‘ language proficiency, concept mapping group has the worst performance in L2 discourse comprehension in the delayed test.3) Learners‘ language proficiency has different influence on the three learning methods. In spite of the significant difference between high-level participants and low-level participants in the free recall group, both of them perform better than encoding methods in the immediate and the delayed test. The result shows that practicing retrieval can enhance learning for both high-level participants and low-level participants. By contrast, high-level participants in the concept mapping group have better learning relative to repeated study group both in the immediate and the delayed test, whereas the result is the opposite for low-level participants. Concept mapping method requires participants to create a concept map of the passage on the basis of comprehension, which raises a high demand for learners‘ language proficiency. So for low-level participants, concept mapping isn‘t a convenience but a burden to learning. In the repeated study group, however, the difference between high-level participants and low-level participants is the least, indicating that both of them are good at repeated study method.Retrieval practice effect is also observed in L2 discourse comprehension in the present study. Practicing retrieval not only produces more learning than maintenance encoding with repeated study, but also more beneficial than elaborative study with concept mapping. Thus, in real teaching practice, diversified learning methods should be developed among students. Teachers should not only attach importance to encoding, but also retrieval‘s promotion of learning. Teachers can combine encoding with retrieval and guide students to use retrieval practices such as free recall, cued recall and recognition to strengthen their learning and understanding of knowledge on the basis of sufficient encoding. Besides, learners‘ language proficiency should be considered in selecting different teaching methods in order to promote their effectiveness.