Investigating Perceived Ownership in Rubber and Third Hand Illusions Using Augmented Reflection Technology

Abstract

Neuroplasticity can be explained as a change in the brain's wiring which is due to the changes in behaviour, environment and neural processes, as well as changes following bodily injury. In the Rubber Hand Illusion a participant is shown a rubber hand being stroked while their real hand is hidden and stroked behind a screen. The participant then perceives the rubber hand to belong to their body in place of their real hand. This was an early example of Neuroplasticity demonstrated by Botvinick and Cohen (1998).

The Rubber Hand Illusion was investigated in the first experiment of this research, along with a video mediated version of this experiment. The data were examined to investigate perceived ownership toward the rubber hand in both experiments. The results suggest that in both experiments, the RHI and the video mediated Rubber Hand Illusion; there was a sense of perceived ownership toward the rubber hand.

The second part of this research investigated a study that suggests it is not necessary for the hand of the participant to be hidden during the Rubber Hand Illusion. The Third Hand Illusion suggest that a participant could be convinced into perceived ownership of a supernumerary limb. The Third Hand Illusion was the second experiment of this research, performed with two conditions using Augmented Reflection Technology, which is a system developed to investigate Neuroplasticity. In the first condition (aTHI) the participants were shown their hands alongside a pre-recorded rubber hand on the screen. The second condition (mTHI) showed the participant their real right hand, a mirror image of their right hand to represent their left hand and a pre-recorded rubber hand. The two conditions investigated whether there was a sense of perceived ownership during the experiment and compared to see in which condition the sensation was stronger. The results suggest perceived ownership in the mTHI condition, with no sense of perceived ownership in the aTHI condition.

The study showed that there was still a sense of perceived ownership towards the rubber hand in both experiments performed through the ART system.