Virtual Reality Archery to quantify the development of Head-Trunk Coordination, Visuomotor transformation And Egocentric Spatial Representation

The role of head and trunk movements must be taken into account to understand how we process spatial information. To date, no robust methodology allows for such investigation; therefore, we created the VRCR platform. It is a virtual reality archery-like serious game for the assessment of head-trunk motor coordination, head-trunk visuomotor transformation, egocentric space encoding and their relationship. In the VRCR, the user controls the arrow trajectory through head and/or trunk rotations, and experimenters can change the visual consequence of such rotations (i.e., rotating the trunk causes the visual field to rotate too). It comes with a pipeline to analyze both spatial performance and motor behavior. Given its game nature, it is suitable for testing children. A demonstrative experiment was performed on adults, 10-11 year-old children and 6-7 year-old children to directly assess whether people at different development stages could preserve their spatial performance once their head-trunk visuomotor transformation was altered. The visuomotor transformation alteration was detrimental for 6 year-old children's spatial performance and head-trunk motor coordination. The same was not true for children aged 10. Such difference suggests the egocentric reference frame transition away from the trunk between 7 and 9 years of age. The experiment demonstrated the platform's usefulness in simplifying the study of such a complex system by disentangling its components.