Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.06.01.127282v1?rss=1 Authors: Zanini, A., Patane, I., Blini, E., Salemme, R., Koun, E., Farne, A., Brozzoli, C. Abstract: Peripersonal space is a multisensory representation of the space near body parts facilitating interactions with the close environment. Studies on non-human and human primates converge in showing that peripersonal space (PPS) is a body-part-centred representation that guides actions. Because of these characteristics, growing confusion conflates peripersonal and arm-reaching space (ARS) that is the space one's arm can reach. Despite neuroanatomical evidence favors their distinction, whether PPS and ARS tap into different spatial representations remains poorly understood. Here, in five experiments we found that PPS differs from ARS in male and female human participants (N = 120), as evidenced both by their performance and the modeling of their multisensory facilitation. We mapped multisensory facilitation in detecting touches at the hand, placed in different locations radially within ARS. Results showed that 1) PPS is smaller than ARS; 2) multivariate modeling of spatial patterns of multisensory facilitation predicts well the position of the participants' hand within ARS; 3) multisensory facilitation maps shift according to changes of hand position, revealing hand-centred coding of PPS, but not ARS; and 4) cross-correlation analyses highlight isomorphic multisensory facilitation maps across hand positions, suggesting their functional similarity to the receptive fields of monkeys' multisensory neurons. In sharp contrast, ARS mapping produced undistinguishable patterns across hand positions, cross-validating the conclusion that PPS and ARS are distinct. These findings call for a refinement of theoretical models of PPS and ARS, which are relevant in constructs as diverse as action and self representation, (social) interpersonal distance, brain-machine interfaces and neuroprosthetics. Copy rights belong to original authors. Visit the link for more info