The impact of multimodal GenAI-Integrated instruction on EFL learners’ speaking proficiency, motivation, and well-being: a mixed-effects modeling approach

The integration of multimodal Generative Artificial Intelligence (GenAI) into language education is transforming the ways learners engage with instructional content and develop communicative competence. In English as a Foreign Language (EFL) contexts, enhancing learners' motivation and well-being is equally important because these factors support sustained engagement and language development. The present study investigated the impact of multimodal GenAI-integrated instruction on EFL learners' speaking proficiency, motivation, and well-being. The participants were 174 Chinese EFL learners recruited from four public universities in central and eastern China. Using a quasi-experimental design, participants were assigned to either an experimental group that received multimodal GenAI-supported instruction through ChatGPT-4o or a control group that learned through conventional text-based materials. The intervention was implemented over eight weeks, during which both groups completed identical curriculum-based speaking tasks. Data were collected at three points: pretest, immediate posttest at the end of the intervention, and an eight-week delayed posttest. Speaking proficiency was assessed through a standardized speaking test; motivation and well-being were measured using validated questionnaires. The data were analyzed using mixed-effects modeling (MEM) to examine changes across time and between groups. The findings revealed significant improvements in speaking proficiency, motivation, and well-being among learners in the experimental group compared with those in the control group. The results indicated that gains achieved through multimodal GenAI-supported instruction were maintained at the delayed posttest. These findings suggest that multimodal GenAI can be effectively incorporated into EFL instruction to create engaging learning environments that support linguistic development and positive psychological outcomes.