How VR-Based Reach-to-Grasp Experiments Can Help to Understand Movement Organization within the Human Brain

This paper examines the potentials of VR technology for studying the neural organization of voluntary human movements. Here, motion studies are based on experimental set-ups in which subjects and/or patients interact with virtual instead of real objects. This VR-based approach is primarily motivated by the exact controllability of computer-generated experimental conditions. Stimuli such as appearance, characteristics, and behavior of objects can be varied and presented separately or in combination. Besides general benefits such as standardization, flexibility, and efficiency, VR provides a means to realize experimental scenarios that are very difficult or even impossible to build when using real, physical set-ups. This feature is demonstrated by the example of reach-to-grasp studies with perturbation, which play an important role for the study of human motor behavior. A first VR-based experiment is described that compares motor behavior when reaching and grasping a real and a virtual cube, respectively. The results of this experiment prove that VR technology can indeed lead to new insights about how the reach-to-grasp movement is organized within the human brain.