May high level processes drive embodiment illusions?

The sense of body has been experimentally studied over the past few decades. A vast amount of work shows that through conflicting multisensory signals it is possible to shift body perception to the point of perceiving a foreign limb or body as one’s own. Such literature has recently been contested by data pointing at the relation between hypnotic suggestibility and other high-level processes and findings previously related to the sense of body ownership. Despite this, experimental paradigms relying on multisensory cues to alter the sense of body result in remarkable behavioral changes. It seems that while top- down processes clearly do play a role in such illusions, so do bottom-up sensory processess. In this study we use sensory cues ecologically unrelated to the body that have previously shown to alter own-body perception (a pitch shift linked to vertical expansion of the finger) together with an attentional task to disentangle if such illusions may be driven mainly by top-down processes or if indeed the conflicting multisensory cues are the driving force. 40 participants are currently undergoing the procedure. Data collection and statistical testing should be finished by the date of this presentation and integrated in the poster.