The role of AI avatars and human instructors in video-based learning: an eye-tracking study on cognitive load and social presence

In plain English

Fifty-one middle-school students in Türkiye watched instructional videos presented by a human instructor, an AI avatar, or a photo-based synchronised video, with eye-tracking recording where they looked. Which kind of presenter it was made no significant difference to achievement, cognitive load, social presence, credibility or mind wandering — but how long students looked at the instructor did: more fixation on the presenter went with higher achievement and stronger social presence, less with more mind wandering. The practical reading is that an avatar presenter is not a penalty, and the design question is whether the presenter holds attention at all.