From Part- to Whole-Body Ownership in the Multisensory Brain

SummaryThe question of how we experience ownership of an entire body distinct from the external world is a fundamental problem in psychology and neuroscience [1, 2, 3, 4, 5 and 6]. Earlier studies suggest that integration of visual, tactile, and proprioceptive information in multisensory areas [7, 8, 9, 10 and 11] mediates self-attribution of single limbs. However, it is still unknown how ownership of individual body parts translates into the unitary experience of owning a whole body. Here, we used a “body-swap” illusion [12], in which people experienced an artificial body to be their own, in combination with functional magnetic resonance imaging to reveal a coupling between the experience of full-body ownership and neural responses in bilateral ventral premotor and left intraparietal cortices, and left putamen. Importantly, activity in the ventral premotor cortex reflected the construction of ownership of a whole body from the parts, because it was stronger when the stimulated body part was attached to a body, was present irrespective of whether the illusion was triggered by stimulation of the hand or the abdomen, and displayed multivoxel patterns carrying information about full-body ownership. These findings suggest that the unitary experience of owning an entire body is produced by neuronal populations that integrate multisensory information across body segments.

► The self-attribution of an entire body is mediated by multisensory integration ► Activity in premotor and intraparietal areas and putamen reflects full-body ownership ► The construction of full-body ownership requires integration across body segments