Disrupted sense of agency-related ownership and disownership increase in the Rubber Hand Illusion

Empirical evidence suggests that body ownership and the sense of agency operate as an interactive system correlated with the level of consciousness during tasks involving modifications in body representation. This study sought to elucidate the nature of this association by documenting the verbal manifestations of this interaction. Specifically, the study aimed to reveal the role of a sense of agency in the individual sensitivity to the Rubber Hand Illusion (RHI). The sense of agency was measured through a post hoc interview wherein participants could verbally express their rubber hand ownership and real hand disownership experiences following the RHI examination. The RHI was induced in 49 healthy, right-handed college volunteers, including 28 males (mean age 28.6) and 21 females (mean age 26.6). Three main scores - ownership, disownership, and proprioceptive drift - were defined to measure individual sensitivity to Rubber Hand Illusion. Verbal reports related to the RHI were analyzed utilizing an automated narrative content analysis toolkit which explored the deeper content of words and stories to identify situation-driven cognitive processes, specifically focusing on the rate of sense of agency and other cognitive variables. The findings indicated that a greater disruption in the sense of agency predicts increased sensitivity to the Rubber Hand Illusion. Therefore, individuals with a lower rate sense of agency exhibit increased malleability in body representation when a rubber hand illusion is induced.