1) The document reviewed over 500 articles on human factors in online education, categorizing them into domains like psychology, technology, physiology, and methodology. 2) It found that psychology and technology were the most prevalent domains, accounting for around 75% of the research. Physiology was the least studied at 1%. 3) Most studies focused on learners and methodology, while educators were largely ignored. The analysis revealed the main research trend examines the "learner-oriented psychological aspects of online education." It identified a need for more research on environments and systems as well as the creators of online content.