Video has become an essential educational tool for enhancing student understanding of learning materials and improving the delivery of educational content. With increasing global attention on artificial intelligence (AI), recent research suggests that the importance of social presence in learning extends to scenarios where the instructor is an AI-generated agent rather than a human. However, the effectiveness of video media has not always been consistent, and there is limited knowledge about the impact of AI-generated videos on student engagement, particularly in the context of foreign language learning. Therefore, this study aims to explore differences in student engagement induced by AI-generated videos for foreign language learning compared to human-generated videos, with the following research question: To what extent do AI-generated videos influence student engagement compared to human-based ones?

Following a 2x2 experimental design, four videos with identical content were created as learning resources for European Portuguese learning. These videos were produced by cross combining the voice and avatar variables, i.e. AI voice & AI avatar, AI voice & human avatar, human voice & AI avatar, and human voice & human avatar. To minimise potential bias and ensure the accuracy of the research findings, participants were randomly allocated to four groups. Each group watched the four types of videos, with the order of the video presentations varying to control for order effects. For student engagement, we assessed the dimensions of focused attention, perceived usability, aesthetic appeal, and reward factor. Linear mixed models with restricted maximum likelihood estimation were used. Our results suggest that AI-generated videos can significantly improve student engagement in foreign language learning compared to human-generated videos, especially in the dimensions of aesthetic appeal, reward factor and perceived usability. Either AI voice or an AI avatar alone can improve student engagement under comparable conditions. However, a significant improvement in engagement is only observed when both voice and avatar are AI-based.

In conclusion, this study provides valuable insights into the influence of AI-generated voices and avatars on foreign language learning. The results suggest that AI-generated videos can be effectively used in foreign language learning or other educational settings, serving as a high-quality alternative to human videos by increasing student engagement. Due to the simplified production process of AI-generated videos, there is promising potential for introducing more flexible and efficient educational tools across the educational landscape.

Keywords: AI-generated videos, student engagement, foreign language learning, short videos.