The Efficacy of Captions on Students' Incidental Vocabulary Acquisition

Abstract

An increasing number of videos enhanced with captions are used in foreign language classes to help second language (L2) learners process authentic input, which is a real challenge for them. This study investigates whether the availability of two types of captions (full captions and keyword captions) facilitates L2 vocabulary acquisition. Fifty-seven adult English-as-a-foreign language (EFL) learners watched an English video clip under one of the following three conditions: full captions (FC); keyword captions (KC); and no captions (NC). After viewing the video clip, the participants immediately completed vocabulary recognition and meaning recall tests. The results from ANOVA indicated that the FC group significantly outperformed the KC group and the NC group on the vocabulary recognition test and the overall vocabulary test (combination of vocabulary recognition and meaning recall tests). Conversely, no significant difference was found between the KC and NC on all vocabulary tests. Furthermore, there was no significant difference between all groups on the meaning recall test. These results suggest that FC help improve L2 vocabulary acquisition among EFL learners. This study does not lend support for the efficacy of keyword captions. Pedagogical implications based on the study findings are discussed.