This study examined the differential effects of text-based online chat and in-person communication on vocabulary acquisition among Iranian English as a Foreign Language (EFL) learners. Forty male EFL students were selected for the study after ensuring homogeneity in proficiency levels through the Oxford Placement Test. Participants were randomly assigned to two experimental conditions: one group interacted via face-to-face dialogue, while the other communicated through synchronous text-based chat. The study aimed to assess the role of computer-mediated communication (CMC) in lexical development. Data analysis was conducted using SPSS (Version 22). Results demonstrated that learners in the text-chat condition achieved significantly higher vocabulary gains than those in the face-to-face group. Furthermore, the CMC group displayed more frequent and successful negotiation of meaning when encountering unknown words. The findings suggest that text-based interaction offers a more conducive environment for vocabulary enhancement compared to conventional spoken interaction.
Siahpoosh et al. (Mon,) studied this question.