Investigating Bodily Awareness in Adults and Children Using Virtual Reality

In the Full Body Illusion, adults can embody a virtual body when provided with certain cues. By manipulating variables such as the movement and appearance of a virtual body, experimenters can identify cues needed to build a stable sense of bodily awareness. Such paradigms are also used with children, to build a picture of how bodily awareness changes with development. Here, we used virtual reality and motion capture to provide participants with a first-person perspective of a virtual body to investigate bodily awareness in adults and children. In Experiment 1 we showed adults a virtual body for 5, 30, or 55 seconds, during which it moved synchronously or asynchronously with their movements, or remained static. After 5s, participants reported experiencing embodiment even when movement was asynchronous. These ratings decreased with further exposure to asynchronous movement but remained high in synchronous and no movement conditions, suggesting that adults embody an avatar seen from a first-person perspective by default. In Experiment 2, adults and children viewed bodies which were either 50% or 100% of their own body size. Both groups perceived the virtual environment to have changed size as opposed to their own body, with the exception of children perceiving their body to have grown in the ‘large’ body condition. Therefore body-relative size perception is roughly adult-like from the age of five, with slightly more tolerance to body growth. In Experiment 3, we piloted the use of skin conductance as a measure of embodiment in a group of adults, in response to a ‘child-friendly threat’. Unlike self-reported embodiment, skin conductance did not differ between visuomotor synchrony conditions. Further work is needed to apply psychophysiological measures of embodiment to children. Overall, the work described here contributes to understanding of bodily awareness across ages, as well as having practical applications in virtual reality design.