The Effect of Input Enhancement on Vocabulary Learning: Is There An Impact upon Receptive And Productive Knowledge?

Abstract

This article reports on a quasi-experimental study investigating the effectiveness of two different teaching approaches, explicit teaching and explicit teaching combined with textual and aural input enhancement used to teach lexical items to elementary level learners of Turkish in a higher education context. Forty participants were divided into two equal groups and given a pre-test measuring productive and receptive knowledge of nine targeted lexical items naming common types of food and drink. Each group was then given sixty minutes instruction on ‘restaurant Turkish’, using a direct communicative approach. Group one (comparison group) received explicit teaching only, while group two (experimental group) received the same teaching but also used a menu where the target words were bolded (textual input enhancement) and listened to the target words modelled by the teacher three times (aural input enhancement). Following the treatment, tests measuring productive and receptive knowledge of the target items were administered. This process was repeated with a delay of two weeks following the treatment. Analysis of gain scores for receptive and productive tests made at the pre-, post- and delayed stage reveal larger gains for the experimental group in each test. These were statistically significant when compared with the comparison group’s scores for production at the immediate post- test stage. Within group tests showed that each treatment had a significant impact on receptive and productive knowledge of vocabulary targeted, with a larger short term effect on the experimental group. Previous studies in this area have tended to focus on the use of input enhancement in relation to the learning of grammatical forms but these results demonstrate some clear benefits when teaching lexis, which have clear implications for further research and teaching.