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Revisiting the Rubber Hand Illusion: Do virtual hands 'feel' touch eyes see, using minimal parameters? Terms of Reference

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Abstract

The mechanisms behind the cognitive processes relating to our sense of body ownership and self-attribution are still not fully understood. This study reproduces and builds upon the Rubber Hand Illusion (RHI), where subjects report the curious sensation of feeling an artificial hand as being their own. Two experiments are conducted. The first investigates if the results of the original RHI can be successfully reproduced using the same experimental design. The second investigates the constraints of the phenomenon using a virtual hand with a resolution of 55%, whilst applying a delay of 300ms. The results support the findings of the original RHI. Subjects in the experimental group exhibited a noticeable drift of 40mm toward the rubber hand, when asked to point to their own left hand; p = .007 and statements regarding ownership of the rubber hand proved significant; p < 0.05. A delay of 300ms in haptic feedback was sufficient to break the illusion in the second experiment, where there was a noticeable drift of-10mm away from the virtual hand for the control group, compared to a 29mm drift toward the virtual hand for the experimental group; p < .001. In addition, an anatomically correct virtual hand with a resolution of 55% was sufficient to create the illusion. In the experimental group 8 out 15 subjects, and 9 out 15 (60%) subjects in the control group felt that the virtual hand was their own, suggesting avatar bodily representations that are anatomically correct/similar elicit a sense of ownership.

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