Incidental vocabulary learning and retention of EFL learners To what extent is topic interest a factor?

Research addressing the effect of interest on learning has been thoroughly discussed in learning theory (Renninger et al., 2014). From this rich research field, topic interest has been put forward as a relevant variable in learning in general (Hidi, 2001; Renninger, 2009), and in L2 reading comprehension (Brantmeier, 2006; Eidswick, 2009). However, research focusing on the extent of its influence on L2 incidental vocabulary learning has been scarce (Lee & Pulido, 2017). Thus, this study sought to explore the relationship between topic interest and L2 vocabulary learning by asking 55 male EFL learners at a technological university in Chile to read texts in two conditions (high topic interest and low topic interest) and then assessing incidental learning and retention of twenty target words. Results suggest that topic interest influenced the vocabulary gains made by learners, and that the relationship between topic interest and vocabulary learning and retention can be mediated by dictionary look-up behaviour. Findings are discussed with a focus on the pedagogical actions that can increase learner topic interest.