Shifting perceptions : exploring with the rubber hand illusion

In two experiments, we explored the boundary conditions for evoking the rubber hand illusion (RHI). In the first study, we hypothesized that we could elicit more vivid RHI experiences using personal cell phones than using wooden blocks as external objects because we interact with our phones and they are familiar objects. The cell phone condition elicited a weak illusory experience but it did not significantly differ from the wooden block condition. In the second study, we hypothesized that manipulating the size of rubber hands used for the illusion would affect size estimates of objects. Participants who experienced a strong RHI with a large rubber hand underestimated the size of small objects more than participants who did not vividly experience the illusion. However, this underestimation bias was stronger before experiencing the illusion rather than afterwards, suggesting that just visual size comparison might affect size estimates rather than experiencing the multisensory RHI. These findings contribute to our knowledge of the RHI by demonstrating that the conditions necessary to evoke the RHI extend to cell phones and rubber hands of different sizes