The role of captioned video in developing speech segmentation for learners of English as a second language

Over three decade’s worth of research into the effects of captioned video on second language learning suggests that it may improve L2 listening comprehension (Vanderplank, 2010). However, there are several limitations to the experimental designs of some early studies in this field (Vanderplank, 2013), thus there is a need for more robust research to be conducted. Mitterer and McQueen (2009) designed an innovative experiment to investigate the effects of captioned video on L2 speech perception. The aim of this research is to build upon their work, primarily by investigating whether repeated exposure to captioned video, delivered by several speakers from a broadly similar variety of English, could (a) lead to improved speech segmentation when listening to speakers that the learner has never heard before, and (b) improved L2 listening comprehension. For example, whether watching a number of documentaries with subtitles could lead to enhanced listening comprehension when watching subsequent subtitles-free documentaries delivered by different presenters.
The main contribution of this study is that it is the first to specifically investigate the ability of participants to segment the speech of (a) previously encountered utterances; (b) different utterances by the same speaker; and (c) different utterances by different speakers of a similar accent. A pre-test / intervention / post-test experimental design was performed multiple times on international university students in the UK. Participants who watched captioned video during the treatment phase, consistently outperformed control groups, which suggests that L2 learners of English can improve their L2 listening skills (and more specifically, their L2 speech segmentation ability) by simply watching same-language subtitled TV programmes on a regular basis.