I Know What You Know: What Hand Movements Reveal about Domain Expertise

Abstract

This research investigates whether students’ level of domain expertise can be detected during authentic learning activities by analyzing their physical activity patterns. More expert students reduced their manual activity by a substantial 50%, which was evident in fine-grained signal analyses and total rate of gesturing. The quality of experts’ discrete hand movements also averaged shorter in distance, briefer in duration, and slower in velocity than those of non-experts. Interestingly, experts adapted by nearly eliminating gestures on easier problems, while selectively increasing them on harder ones. They also strategically produced 62% more iconic gestures, which serve to retain spatial information in working memory while extracting inferences required to solve problems correctly. These findings highlight the close relation between hand movements and mental state and, more specifically, that hand movements provide an unusually clear window on students’ level of domain expertise. Embodied Cognition and Limited Resource theories only partially account for the present findings, which specify future directions for theoretical work.