Validation of a Virtual Reality Environment to Study Anticipatory Modulation of Digit Forces and Position

The aim of this paper is to validate a virtual reality (VR) environment for the analysis of the sensorimotor processes underlying learning of object grasping and manipulation. This study was inspired by recent grasping studies indicating that subjects learn skilled manipulation by concurrently modulating digit placement and forces as a function of the position of object center of mass (CM) in an anticipatory fashion, i.e. by modulating a compensatory moment before the onset of object manipulation (object lift onset). Data from real and virtual grasping showed a similar learning trend of digit placement and forces, resulting in successful object roll minimization. Therefore, the overall behavioral features associated with learning real object manipulation were successfully replicated by the present VR environment. The validation of our VR experimental approach is an important preliminary step towards studying more complex hand-object interactions.