Virtual Reality platform for functional magnetic resonance imaging in ecologically valid conditions

Functional magnetic resonance Brain Imaging (fMRI) is a key non-invasive imaging technique for the study of human brain activity. Its millimetric spatial resolution is at the cost of several constraints: participants must remain static and experience artificial stimuli, making it difficult to generalize neuroscientific results to naturalistic and ecological conditions. Immersive Virtual Reality (VR) provides alternatives to such stimuli through simulation, but still requires an active first-person exploration of the environment to evoke a strong sense of presence in the virtual environment. Here, we report how to compensate for the inability to freely move in VR by leveraging on principles of embodiment for a virtual avatar, to eventually evoke a strong sense of presence with a minimal motion of the participant. We validated the functionality of the platform in a study where healthy participants performed several basic research tasks in an MR-specific immersive virtual environment. Our results show that our approach can lead to high sense of presence, strong body ownership, and sense of agency for a virtual avatar, with low movement-related MRI artifacts. Moreover, to exemplify the versatility of the platform, we reproduced several behavioral and fMRI results in the perceptual, motor, and cognitive domains. We discuss how to leverage such technology for neuroscience research and provide recommendations on efficient ways to implement and develop it successfully.