The effects of gesture frequency and reduced video speed on virtual human persona and learning outcomes
Educators use various strategies to increase listening comprehension for nonnative English speakers in the classroom and multimedia environments. Research on audio reduction has shown mixed results, whereas a study that enhanced (doubled) virtual human gesturing found increased listening comprehension with procedural information (Davis and Vincent, British Journal of Educational Technology 50:3252-3263, 2019). This research examined the use of virtual human gesture frequency (enhanced, average, no) and video speed (normal, reduced 25%) on participant satisfaction, perception of agent persona, and learning outcomes with procedural information. Structural equation modeling was used to analyze the data from 234 multinational university students. The results indicated that normal video speed significantly increased satisfaction compared to reduced speed; agent persona was rated significantly higher with agents that gestured compared with the no-gesture condition; and enhancing the gesture frequency significantly increased learning outcomes compared to the average and no-gesture conditions. These findings support previous studies that indicated enhanced gestures significantly increase the learning of procedural information. Also, agent gesturing increased the perception of the agent as having more persona, which supports systematic review findings that gesturing is a principal moderator for agent persona (Davis et al., Journal of Research on Technology in Education 53:89-106, 2021). However, this research provides evidence that a 25% reduction in video speed might be too slow to maintain satisfaction with advanced foreign language users and that less reduced rates such as 15% or 10% need to be considered. Finally, this research puts forth a gesture design framework for designers to create gesturing virtual humans in multimedia environments.