RESUMEN
Spatial understanding of complex anatomical concepts is often a challenge for learners, as well as for educators. It is even more challenging for students with low mental spatial abilities. There are many options to teach spatial relationships, ranging from simple models to high-end three-dimensional (3D) virtual reality tools. Using a randomized controlled trial design, this study explored the use of a unique combination of deictic and iconic hand gestures to enhance spatial anatomical understanding, coining the term "Air Anatomy". The control group (n = 45) was given a lecture on the anatomy of extraocular muscles, while the intervention group (n = 49) received the same lecture including "Air Anatomy" hand gestures. When compared to the control group, the post-test scores for the intervention group were significantly higher for basic recall (P < 0.001; Mann-Whitney U test) and for the application of knowledge (P = 0.015; Mann-Whitney U test). Students with low to moderate spatial ability (as assessed by a mental rotation test) were found to benefit most by this technique. Students in the intervention group also reported a lower extrinsic cognitive load and higher germane load, when compared to the control group. An instructional skills questionnaire survey indicated the effectiveness of this technique in improving overall classroom experience. Feedback of the students in the intervention group was also favorable for instruction using "Air Anatomy". The study suggests that "Air Anatomy" is a useful, "no-cost", accessible method that aids spatial understanding of anatomical concepts.