Technology-mediated teaching vocabulary: exploring EFL learners’ depth and breadth of lexical knowledge

Drawing on Mayer's Cognitive Theory of Multimedia Learning, the present study aims to examine the effectiveness of technology-mediated teaching vocabulary in the form of multimedia glosses on EFL learners' depth and breadth of lexical knowledge. The study was conducted with 91 male and female undergraduate students at a lower-intermediate level of English proficiency in Iran. Participants of the study were randomly assigned into two-variable group contrasts, experimental (text + visual) and control (text-only) groups. They attended 16 reading sessions once a week during which the experimental group practiced computerized reading texts with pop-up text and picture glosses and the control group practiced reading similar texts with pop-up text only. The relative efficacy of teaching activities in vocabulary learning was assessed by using the Word Associates Test for measuring lexical depth and the Updated Vocabulary Levels Test for measuring the lexical breadth before and after the intervention program. To scrutinize the data, ANCOVA and t-test have been done. Results of ANCOVA revealed that the experimental group outperformed the control group in both tests, and the result of the t-test specified that participants kept the scores in the Vocabulary Levels Test significantly higher than the Word Associates Test in the outperforming group. This means that using multimedia glosses in teaching vocabulary has a significant effect on improving both the breadth and depth of lexical knowledge of EFL learners. However, the effect is more significant on breadth than depth of lexical knowledge. The study by analyzing separate measurements of the breadth and depth of vocabulary knowledge of EFL learners provided original research in vocabulary teaching and learning and offered pedagogical implications for language teaching.