Brain mechanism involved in the real motion interaction with a virtual avatar

Purpose: Feeling sense of full immersion in computer-generated interactive environments often occurs when the user is enjoying the contents and physiologically and behaviorally responding to the events from that world as if they were real. In this state, the individual may feel embodied in the simulated world even more than in the real world. Although the method of interaction could influence this embodied state during immersive experiencing, the brain mechanism has not yet been investigated. Here we directly investigate brain activities related to an embodied state according to the type of interaction. Methods: Our method uses fMRI scanning during interaction with a virtual avatar using a real-action paradigm and using a simple button as a control task. Results: As the results, we observed the parietal lobe’s laterality corresponded to the type of interaction, the left parietal lobe for action task and the right one for the button click condition. In addition, there was a correlation between the motor cortex activities and the co-presence score for realaction condition. The parietal lobe’s laterality is related to transformation of self egocentrically or allocentrically from a 1st or 3rd person perspective. Conclusions: Our results provide direct evidence for the involvement of a 1st person perspective embodiment process into a simulated world, particularly into self-avatar, when individual experiences involve a more real-action based interaction method. In contrast, when interacting with simple button-click method, the 3rd person perspective simulation process is recruited for the interaction by controlling the self-avatar rather than experience by oneself with the worldrestrictio