Electronic International Standard Serial Number (EISSN)
1879-0445
abstract
Almost every bodily movement, from the most complex to the most mundane, such as walking, can generate impact sounds that contain 360° spatial information of high temporal resolution. Given the strong connection of auditory cues to our body actions, and the dependency of body-awareness on the interaction between peripheral sensory inputs and mental body-representations, one could assume that audition plays a specific role in this interaction. Despite the conclusive evidence for the role that the integration of vision, touch and proprioception plays in updating body-representations [1,2], hardly any study has looked at the contribution of audition. We show that the representation of a key property of one's body, like its length, is affected by the sound of one's actions. Participants tapped on a surface while progressively extending their right arm sideways, and in synchrony with each tap participants listened to a tapping sound. In the critical condition, the sound originated at double the distance at which participants actually tapped. After exposure to this condition, tactile distances on the test right arm, as compared to distances on the reference left arm, felt bigger than those before the exposure. No evidence of changes in tactile distance reports was found at the quadruple tapping sound distance or the asynchronous auditory feedback conditions. Our results suggest that tactile perception is referenced to an implicit body-representation which is informed by auditory feedback. This is the first evidence of the contribution of self-produced sounds to body-representation, addressing the auditory-dependent plasticity of body-representation and its spatial boundaries.