Shaping the bodily self: exploring the influence of early attachment experiences on body ownership

Body ownership is commonly studied using the rubber hand illusion (RHI), an experimental paradigm that induces a temporary feeling of owning a fake hand. Although the illusion demonstrates that multisensory integration is at the core of body ownership, factors like personality traits also modulate the experience and/or intensity of the illusion in a top-down manner. Here, we investigated the role of early attachment experiences as a factor that could influence body ownership. The RHI was administered at baseline and after a short-term activation of the attachment system using the Adult Attachment Projective (AAP). Proprioceptive drift, subjective ownership, and disownership were compared between the two conditions. Participants' attachment style (Free, Dismissing, and Entangled), as determined by the Adult Attachment Interview (AAI), was considered a stable, between-subject (trait-like) index of adult attachment representations. The RHI effects were modulated by the attachment style, but not by the transient activation of the attachment system. Specifically, proprioceptive drift was larger in the synchronous compared to the asynchronous condition only for participants with the Free attachment style, whereas the subjective aspect of the RHI was not modulated by attachment style. These results suggest that individuals with Free attachment style are more sensitive to the multisensory integration underlying the RHI than individuals with Dismissing or Entangled attachment styles, which may reflect greater flexibility in visuo-proprioceptive recalibration under ambiguity. Thus, early attachment experiences may selectively influence the recalibration of lower-level body-related visual and proprioceptive information, but not the higher-level subjective attribution of body parts to oneself.