Human Information Science Laboratory, NTT Communication Science Laboratories, 3-1, Morinosato-Wakamiya, Atsugi-shi, Kanagawa-ken, 243-0198, Japan, asai.tomohisa@lab.ntt.co.jp.
2 papers in the library · 50 citations · publishing 2015-2017
The rubber hand illusion (RHI) makes people feel that a fake hand is their own when they see it stroked in sync with their own hidden hand. This illusion typically causes a sense that their real hand has shifted toward the fake hand (proprioceptive drift). Two experiments show that participants' actual hand, resting on a movable board, physically moved toward the rubber hand during synchronous stroking. Even when the board was fixed, participants unconsciously pushed force toward the rubber hand. These results suggest that awareness of one's body and one's actions are tightly linked, forming a unified sense of self as a single agent.
In 96 healthy adults, lower gray matter volume in the insular cortex was linked to greater reported malfunction in the sense of ownership over one's body, as measured by the Embodied Sense of Self Scale. No such relationship was found for the sense of agency or narrative self. This suggests that the feeling of ownership may rely on distinct brain structures, and the scale could help screen for such neural correlates.